I think it's because the image generation models can generate very low res images (64x64) and then have a slightly different model that upscales them (still wit

I think it's because the image generation models can generate very low res images (64x64) and then have a slightly different model that upscales them (still with context) to 1024 or whatever. With audio, there's no similar "global" upscaling. Although maybe it would work, generating with a very low sample rate and upscaling that..