Continental VDO headunit

[tewfiks]

Hello All. I replaced the Becker unit with a VDO/Contintental unit and I intermittently get a loud "pop" sound when I start the car. The sound is emitted from the speakers. I have checked and rechecked the ground on the radio. Any ideas on what to look for next?
Thanks

 

[LWB250]

Just for grins, check your connections for constant power and switched power. When I was using these in the R129 and W126 there were issues with the wiring conventions on these two wires being switched or reversed compared to what was in the stock harness. Are you losing settings when you shut it off?

Dan

 

[tewfiks]

No I am not loosing the settings on the radio. Also, the antenna will start to extend regardless of whether the radio is on or not when I start the car. It will extend about 5-6 inches and then retract if the radio is off.
Thanks Dan