Another Bluetooth module to test. This one is the KCR-86B v4.0. No idea where I got it (probably Ebay), but they're available all over the interweb. This module is Bluetooth 4.0, obviously.
No USB and TF card socket connections on this one, but it does have a stereo aux input. It has LED indicator...
I'm tinkering with various cheap Chinese Bluetooth modules these days. This one is the KCX BT003 - about $3.50 Canadian. I bought mine at icstation.com, but they're available all over the interweb. This module is Bluetooth 4.2. It does MP3, WMA, WAV, and FLAC, and claims to be lossless.
This board...