@Parzival This could be quite easy. I have done it with basic audio amps to send music from a phone to a speaker project. Not done it with a Pi but no reason why it wouldn't work. Just buy a USB Bluetooth dongle from eBay for less than £5 and plug a jack lead from the pi to the USB dongle. It can now pair so the audio out from the jack can be transmitted. Use a spare USB socket for a power source for the dongle.
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