Just thinking this issue through a touch more…
Whether or not the assignment is the issue for the OP, I wonder if the QuDrive stereo playback page could have a warning if ST3 isn’t being routed from the QuDrive (i.e. USB sourced “preamp” and global USB source set to QuDrive)
Should be a relatively simple addition to the screen – maybe just turn the channel red if it’s *not* correctly routed for playback
Similarly for the MTK playback page – each channel could be turned red if *not* routed correctly.
Just a hint for the user…
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