I recently bought ERGO BT-690 wireless headphones. They work perfectly on my phone and work on an old laptop (though you have to put the output device to headset in order to use the mic). My PC uses a 4.0 Bluetooth dongle. When I connect them, it says connected voice, music and I can listen to stereo just fine. If I try to use the microphone or headset output (even when clicking test in device manager), the sound stops even if I go back to stereo output and the headphones will fail to disconnect. Also, audio control panels will lag like hell. I've tried rebooting the computer and re-plugging the dongle. There's no drivers for the headphones. I installed the drivers for the dongle, but the headphones completely failed to work, so I went back to the windows default ones.