USB loopback from DSP chip

I saw that it is possible to loopback audio from the BP1048 B2 chip. (Arylic uses BP1064?)

This is a useful feature as it means the digital output signal from the DSP can be recorded directly in Audacity etc. You send music through USB to the DSP chip, tune the sound to your taste and then record it digitally in real time. (You probably can also record analog in and Bluetooth in the same way, but I never tried.)

Arylic uses the BP1064 on the devices I have, B50 etc. However, this feature seems not to be available when connected by USB to a computer.

Can USB loopback be enabled for the BP1064 devices with a firmware update?