T8S AUX Sends as Inputs?

Our lead singer plugged his blue tooth receiver INTO our T8S AUX Sends 1 & 2. And it worked. He played break music from his phone via an outboard blue tooth receiver plugged in to an output.

How is this even possible?

On a possible related note, all of our vocal inputs dropped out for a period of about 10 seconds during a performance . Something like an email alert hit? No other sound, just muted channels and then they all popped back in.

So weird, and now he refuses to connect the thing through normal input channels. Any thoughts, theories, ideas appreciated!

The T8S manual says that AUX 1 and 2 are outputs; dedicated Aux Input channels are 9/10.

I can’t think of a reason why AUX Sends can be used as inputs other than electronically they are able to but for whatever reason Bose does not support such usage.