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I already have a full STT → LLM → TTS → telephony stack in production, yet callers still hear obvious lag, awkward pauses and a robotic tone. I’m not looking for a rebuild; I need an expert who can dive into the existing codebase and tune it for truly human-sounding conversations. Your main target area is the Text-to-Speech component, though every tweak must be validated end-to-end. The agent must speak Indian English naturally and switch to Hindi when a caller does. Support for other accents is a nice bonus but not essential. Key TTS fixes I expect: • Pronunciation accuracy • Voice naturalness • Response speed Scope of work – Profile the complete pipeline to locate bottlenecks (latency, buffering, audio encoding). – Implement low-latency TTS strategies or swap voices if needed while preserving the existing architecture. – Optimise turn-taking so interruptions are handled smoothly and the agent never gets “stuck.” – Fine-tune prosody, pacing and intonation until the disclosure “This is an AI-powered call” is the only clue it’s synthetic. – Regression-test with live calls and supply before/after recordings that clearly demonstrate the improvements. Acceptance criteria 1. Average round-trip response time in live calls ≤ 800 ms. 2. No audible stutter or clipped words in a 10-minute stress test. 3. Pronunciation errors reduced by at least 90 % compared to baseline sample. 4. Deliverables: optimised code/configs, test logs, and the comparative audio files. If you have proven, real-time voice-agent experience, let’s make this voice sound human.
Project ID: 40643037
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Hi, saw your post about the lag and robotic tone on your voice agent. The usual win is streaming TTS chunk by chunk with barge in on the first frames. Which TTS are you on now? Try mine: [login to view URL] username: admin password: admin1234, an AI call centre I built for JS Bank. Happy to start on a small milestone so you can judge it. Regards, Zohaib
₹8,000 INR in 7 days
1.2
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23 freelancers are bidding on average ₹8,685 INR for this job

Having clocked in 9+ years of expertise in web development and mobile app development, I know exactly what it means to dive into an existing codebase and optimize it for top-notch performance. My skills span across multiple languages including Java, PHP, .NET, HTML5, CSS and more. More so, I have hands-on experience in AI development which further solidifies my understanding of your project parameters. My company and I are devoted to providing the best possible IT services for our clientele, turning ideas into reality being our forte. We can creatively use our skills to validate end-to-end tweaks on your system to rectify lags, unnatural responses and robotic tones. Moreover, employing me means you're choosing a throughbred who can seamlessly switch between English and Hindi while speaking naturally in both accents. While I understand that other language support is not prioritized at the moment, my previous experiences have instilled a great deal of unyielding curiosity for unique challenges. Choose me so we can fine-tune prosody, pacing and intonation until the disclosure “This is an AI-powered call” is the only clue it’s synthetic.
₹17,000 INR in 7 days
5.2
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I'd love to help you optimize your existing STT → LLM → TTS → telephony pipeline for faster, more natural, and interruption-friendly voice conversations without rebuilding the architecture. I have experience with AI voice systems, speech synthesis, NLP, and real-time application optimization, focusing on latency reduction, audio quality, turn-taking, and reliable end-to-end testing. ✅ Low-latency TTS optimization and audio pipeline profiling ✅ Natural Indian English and Hindi pronunciation improvements ✅ Smooth interruption handling, buffering, prosody, and pacing ✅ Live-call regression testing with before/after performance analysis I'd be happy to discuss your requirements and share relevant work samples during the interview. Looking forward to working with you!
₹10,000 INR in 2 days
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Getting round-trip latency under 800ms while still handling natural code-switching between Hindi and Indian English is where most voice pipelines hit their limit, that turn-taking smoothness usually comes down to how tightly the STT, LLM, and TTS stages are pipelined rather than run sequentially. Relevant work includes the AI Voice Receptionist, built with ElevenLabs and OpenAI for real-time conversational audio, and the Lead Enrichment Pipeline, focused on structured, low-latency automated workflows. Portfolio: https://www.freelancer.pk/u/UmairBuildsAI I'd start by profiling the full pipeline to isolate where latency and buffering actually originate, then tune the TTS layer for pronunciation and prosody while testing low-latency voice options, optimize turn-taking so interruptions don't stall the agent, and validate everything with live call regression tests and before/after recordings showing the improvement. Let's connect on a call and discuss. Best Regards, Umair
₹1,500 INR in 7 days
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Hello There, Couple of quick question: * **Is the main challenge reducing the robotic feel of the current AI voice agent, or do you also need improvements to interruption handling, response latency, pauses, tone, and natural turn-taking during live calls?** * **Which voice/telephony stack are you currently using, and can we access the existing call recordings and conversation flow to identify where latency, unnatural responses, or awkward interruptions are happening?** We have experience in **optimizing AI voice agents for natural real-time conversations with improved voice quality, latency, interruption handling, contextual responses, turn-taking, speech-to-text/text-to-speech pipelines, and telephony integrations.** Our company has 17+ years experience in IT service development. You might see our profile is new, but not new in this business. Kindly open the chatroom, we can discuss your requirement in detail. Also release the payment once we are finish the task as you prefer. Give us a opportunity and we won't fail you. Thanks, Sandeep K.
₹1,500 INR in 7 days
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As an AI Automation specialist, with over a decade of experience and more than 500 successfully delivered projects under my belt, I'm confident I'll be the perfect fit for your Natural AI Voice Call Optimization project. From my understanding, you're not looking for an entire rebuild but a tweak and fine-tuning of your existing system to make it sound more human-like. This is precisely what I specialize in - taking already established systems and optimizing them for enhanced performance. Let's talk about transforming your already impressive STT → LLM → TTS → telephony stack into one that eliminates all noticeable lags, robotic tone, and awkward pauses during conversations. Nailing the Text-to-Speech component is my area of expertise and I can assure you that I will dive deep into your current codebase to locate and resolve any bottlenecks affecting latency, buffering, and audio encoding. Regards Akif A
₹7,000 INR in 5 days
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Hi, I can help optimize your existing STT → LLM → TTS → telephony pipeline without rebuilding the system from scratch. I can profile the complete call flow to identify latency, buffering, audio encoding, and turn-taking bottlenecks, with primary focus on improving TTS pronunciation, naturalness, and response speed. I can tune Indian English pronunciation and Hindi language switching, optimize prosody, pacing and intonation, and improve interruption handling so conversations feel smoother and more natural. I’ll validate every TTS change through the complete telephony pipeline and compare the baseline against the optimized version using real-call testing. Deliverables will include optimized code/configuration, latency and stress-test logs, pronunciation test results, and before/after audio recordings. I’d be happy to review your existing stack, TTS provider/configuration, and baseline recordings first, then confirm the optimization plan, milestones, and timeline.
₹8,000 INR in 10 days
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Hi, I'd be glad to help optimise your existing STT → LLM → TTS → telephony stack for truly human-sounding conversations, focusing on the Text-to-Speech component to improve pronunciation accuracy, voice naturalness, and response speed. To achieve this, I will profile the complete pipeline to locate bottlenecks, implement low-latency TTS strategies, optimise turn-taking, and fine-tune prosody, pacing, and intonation. I will utilise my experience in AI development, speech synthesis, and natural language processing to ensure the agent speaks Indian English naturally and switches to Hindi when a caller does. My approach will involve regression-testing with live calls and supplying before/after recordings to demonstrate improvements. I can cover: • Optimised code and configurations for the TTS component • Test logs and comparative audio files to demonstrate improvements • Implementation of low-latency TTS strategies to reduce response time • Fine-tuned prosody, pacing, and intonation for natural-sounding conversations • Regression testing with live calls to ensure smooth turn-taking and interruption handling I work with clear daily progress updates and honest scoping. Please share your existing codebase and specifications, and I can get started right away. Best regards, Gagan
₹5,000 INR in 14 days
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Hi! This is exactly the kind of voice-agent tuning work I enjoy — because “Hello… [awkward 2-second silence] …sir” is not exactly the human experience we’re aiming for ? I can work directly with your existing STT → LLM → TTS → telephony pipeline without rebuilding the architecture. I’ll profile end-to-end latency, buffering, codec/streaming behavior, turn-taking, barge-in handling, and TTS generation to identify where the lag and robotic feel are coming from. My focus will be: Low-latency streaming TTS and faster first-audio response Natural Indian English + Hindi switching Pronunciation, pacing, prosody and intonation tuning Smooth interruption/barge-in handling Eliminating clipped words, stutters and dead-air pauses Benchmarking against your ≤800 ms live-call target I’ll deliver optimized code/configs, latency/test logs, and before-vs-after call recordings so the improvement is measurable, not just “sounds better on my laptop.” ? Happy to review your current stack and start with a latency/TTS audit before touching product
₹7,000 INR in 7 days
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Hi, I have similar experience and confident to handle the project. Please get in touch to save your time and you will get your project fixed to your satisfaction. Best , Goran
₹12,000 INR in 7 days
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Hi, I’m interested because I had a very similar issue in my own voice-agent project, DentSignal. The voice itself sounded good, but parts of the audio were getting chopped—especially near the start of playback. I traced it through the streaming and telephony path and found the real issue: an absolute timeout was clearing the active turn even while audio chunks were still arriving. I removed that bad cutoff while keeping the important safeguards for idle recovery, barge-in, and queue limits. After that, the audio became smooth with no clipped words. That is why I’m confident I can help without rebuilding your stack. I would first trace your STT → LLM → TTS → telephony timings, then check chunk delivery, buffering, codec/resampling, first-audio delay, and interruption handling. From there I’ll make targeted fixes around the actual bottleneck, including Indian English/Hindi voice setup and more natural turn-taking. You’ll get a clear before/after report, updated code or configs, and a practical 10-minute stress test. I will not promise 500 ms before seeing the baseline, but I’ll make it measurable from day one and focus on the limiting stage. Can you share the current STT, LLM, TTS, and telephony providers, plus any short sample recording or logs?
₹4,999 INR in 6 days
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Hello, I’m an AI Engineer experienced in Python, FastAPI, LLM pipelines, real-time AI systems, and voice-agent architectures. I understand that you are not looking for a rebuild, but for expert optimization of your existing STT → LLM → TTS → telephony pipeline. I would begin by profiling the complete live pipeline to establish a baseline for STT latency, LLM generation, TTS time-to-first-audio, buffering, encoding, network overhead, and turn-taking delays. My focus would be: • Reducing TTS latency and time-to-first-audio • Improving Indian English pronunciation and naturalness • Smooth Hindi/English switching • Optimizing prosody, pacing, pauses, and intonation • Eliminating stutter, clipping, and unnecessary buffering • Improving interruption/barging-in behavior I would preserve your current architecture wherever possible and only change components when measurements justify it. TTS improvements would also be validated end-to-end through real calls rather than isolated benchmarks. I can provide before/after recordings, latency measurements, stress-test results, regression logs, optimized configurations, and clean source-code changes. I understand the acceptance criteria, including the ≤800 ms round-trip target, 10-minute stress test without audible issues, and measurable pronunciation improvement. I’d start by profiling the current production pipeline, identifying the highest-impact bottlenecks, and then systematically optimizing and validating each change.
₹5,000 INR in 8 days
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Being a Senior Full-Stack & App Developer with over 5 years of experience and a track record of creating high-performance mobile apps and APIs, I believe I possess the skills you need to fine-tune your Natural AI Voice Call system. I have an in-depth understanding of key technologies such as React Native, Android, Java, and REST APIs – all of which are essential components in your existing stack. Moreover, my proficiency in working with voice-based technologies aligns perfectly with your voice-focused project. From handling pronunciation accuracy, response speed, to ensuring voice naturalness, my expertise adds real value to this project. Not only that, but I'm also experienced in optimizing turn-taking for smooth interactions – guaranteeing that calls never get stuck or sound robotic. Client satisfaction and producing tangible results drives me. That's why I'm obsessed with testing and debugging applications until they are perfect. For your project, this means driving audio latency down to meet your desired trip time and providing before and after-recordings that clearly highlight the humanization I will guarantee for your AI system. Make the choice that promotes real improvement and choose me.
₹7,000 INR in 7 days
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I work with production voice AI pipelines regularly (STT/LLM/TTS/telephony), so this is a tuning problem I recognize well. Most robotic-sounding TTS in production comes from three things: chunking text too late before synthesis starts, not streaming TTS output as it generates, and not handling barge-in properly so the agent talks over itself. Plan: profile the pipeline first to find where the 800ms budget is actually going (STT latency, LLM time-to-first-token, TTS synthesis start, network hops), then fix streaming so TTS starts speaking before the full response is generated, tune VAD and turn-taking thresholds for clean interruption handling, and adjust prosody settings specifically for the Indian English and Hindi switch, since that is usually where pronunciation models default to something generic. I can turn the diagnosis and first round of fixes around in about 3 to 4 days, then iterate against your live call recordings. What TTS engine and telephony layer are you currently running?
₹7,000 INR in 7 days
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Hi, I can optimize your existing production STT → LLM → TTS → telephony pipeline without rebuilding it. My focus would be reducing latency, improving Indian English/Hindi pronunciation, and making turn-taking sound natural. My approach: • Profile the complete live pipeline to identify TTS generation, buffering, encoding, network, and turn-taking bottlenecks • Optimize streaming TTS, audio chunking, buffering, codec/sample-rate handling, and connection reuse • Evaluate alternative voices/models where necessary while preserving your architecture • Tune pronunciation, phoneme handling, prosody, pacing, pauses, and Hindi/Indian English language switching • Improve interruption/barge-in handling so the agent stops and resumes naturally • Run repeatable end-to-end latency and stress tests using real telephony conditions • Compare baseline vs optimized recordings and quantify pronunciation/latency improvements I’ll target the ≤800 ms round-trip requirement and investigate every component contributing to that budget rather than optimizing TTS in isolation. Deliverables: 1. Optimized production code/configuration 2. Before/after latency and pronunciation measurements 3. 10-minute stress-test results 4. Comparative audio recordings 5. Concise technical handover documentation
₹12,000 INR in 7 days
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Hello, I'm Bharghav, and I bring over 10 years of experience matching job skills to specific project requirements. My focus on Android development aligns perfectly with your need for optimizing the Text-to-Speech component of your existing system. I understand you're looking for a tuned solution to minimize lag, awkward pauses, and robotic tones in voice calls. I will profile your pipeline, implement low-latency TTS strategies, and enhance prosody and pacing to ensure natural interactions. My approach includes thorough regression testing with live calls to demonstrate improvements clearly.
₹8,750 INR in 3 days
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Hi — 800 ms is achievable, but only if every stage streams. The lag you describe usually isn't a slow model, it's waiting for complete outputs. First find where time goes: timestamp four points per turn — STT final, LLM first token, TTS first audio byte, playback start. Most teams optimise the wrong stage because they only measure end-to-end. That profile takes an hour and usually shows one stage owning 60% of the latency. What typically fixes it: - Stream TTS. If synthesis finishes before playback starts you've spent 400-800 ms already. Begin audio at the first sentence boundary of the LLM stream. - Pronunciation is a lexicon problem, not a voice problem. Indian names and numerals get mangled by every stock voice; a phoneme lexicon fixes those permanently, while swapping voices just moves them. - Hindi switching: the real case is code-mixed ("aapka order ready hai"), so a multilingual voice beats detect-then-swap, which leaves audible seams mid-sentence. - "Gets stuck" is almost always endpointing. VAD too aggressive cuts callers off, too lax adds a second of silence. Barge-in needs playback killed mid-buffer. I build this stack professionally — streaming STT/LLM/TTS with barge-in, sub-second. Hindi is my working language, so I can judge the output, not just the metric. Questions: 1. Which TTS and telephony provider today? 2. Is the LLM streaming or awaited in full? 3. Can you share one baseline recording? Ronak — 8+ yrs real-time voice AI.
₹6,500 INR in 10 days
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With a proven track record in AI Voice Agents, particularly optimizing text-to-speech systems, I'm confident that my skills and experience are an excellent match for your project. I understand the importance of creating an authentic, human-like experience with your callers and can ensure a seamless transition between Indian English and Hindi. While maintaining your existing system architecture, I will thoroughly profile your pipeline to identify and address any bottlenecks. My expertise lies in enhancing the pronunciation accuracy, voice naturalness, and response speed which aligns perfectly with your scope of work. Additionally, my experience goes beyond just the technical implementation. As an end-to-end product developer, I take ownership of not only coding but also planning, UI design, backend engineering, cloud deployment, and ongoing support. This means you can rely on me for the full lifecycle of your project and there's no need to coordinate multiple teams or freelancers.
₹7,000 INR in 7 days
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