Added AUX cable to my OEM Blaupunkt HU 2 years before. Last year added Bluetooth headset to it with 'Bluedio Av890', but its dead within 4 months. Now added Sony Bluetooth Headset SBH20 to it & its working fine as now. Advantage of using Bluetooth headset instead of Bluetooth receiver is that it supports call too. Reason why I opted AV890/SBH20 over other BT headset is that it has separate charging port where as most other BT headset has same audio port as charging port. So either can listen music or charge it & can't do both same time.