Currently using a Motorola HS820 with a Kensington USB dongle for BT Pairing.  It pairs successfully. After sometime, the audio sound completely cuts out, but it stays paired.  This is a PC setup and I'm only 3 feet away from the PC.  I have to disconnect the Motorola and restart the pairing connection all over.  The time is 5 min to 30 min before it cuts out.