It was Edwin who replied... I also asked, if they would use Tenor TE7022L as replacement for PCM2706 USB chip... but no answer.
What disappointed me a bit is that they probably won't make new modules for Sparrow. It's a pitty, because they introduced really good concept of upgrading their "boxes", but on the other hand, audio-gd is not planning to introduce new modules, which is simply killing the purpose it was made for.
Strange, because I don't see the need for a lot of other modules? What did you have in mind? He obviously will have to address the USB question, but what else?