1B is actually huge for a TTS model. Here's an 82m model with probably the most stable/coherent output of all the open weights tts models I've tested: https://huggingface.co/spaces/hexgrad/Kokoro-TTS
But if you mean zero-shot cloning, yeah they all seem to have those slurred speech artefacts from time to time.
If you're doing a home lab voice assistant 1B is nice, because on a 12gb gpu you can run a moderately competent 7b LLM and two 1b models; 1 for speech to text and also text to speech, plus some for the wake word monitor. Maybe in a couple of years we can combine all this into a single ~8b model that runs efficiently on 12gb gpu. Nvidia doesn't seem very incentivized right now to sell consumer GPUs that can run all this on a single consumer grade chip when they're making so much money selling commercial grade 48gb cards.
1B is actually huge for a TTS model. Here's an 82m model with probably the most stable/coherent output of all the open weights tts models I've tested: https://huggingface.co/spaces/hexgrad/Kokoro-TTS
But if you mean zero-shot cloning, yeah they all seem to have those slurred speech artefacts from time to time.