These USB ports power down when the device is turned off so if you wanted it to always charge even when the receiver was off I'd plan on getting power from the wall.
I have a Pioneer VSX-530-K audio receiver connected to my TV via optical cable. The receiver powers my wired Bose speakers. The receiver does not have bluetooth out capability. I would like to purchase a bluetooth transmitter and plug it into the headphone jack on the receiver so I can utilize bluetooth headphones through the receiver. My question is: There is a usb port on the front of the receiver. Can I use that port to continually charge the bluetooth transmitter, and will it charge when the receiver is plugged into an A.C. outlet, but the receiver is not powered on.
Thanks for any help or suggestions.

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