The Teensy 4.1 board has an 8MB W25Q64JV as opposed to the 2MB flash
on the Teensy 4.0. This largely doensn't matter for TinyUsb, except
when you attempt to access any memory in the flash above the 2MB
boundary, when it fails with a hard fault.
I believe that there is a mistake in the definition of TUD_AUDIO_HEADSET_STEREO_DESCRIPTOR. The nitfs in the audio descriptor is always 3 regardless of ITF_NUM_TOTAL.