hi i have had a sony stereo fitted by a dealer but every so often it looses all presets it has been back a couple of times even had a different sony stereo fitted but still the same any ideas anyone as it is doing my head in and the dealers
ps its a 2002 a6 avant

 

Have someone check the wiring harness that was used for the install... the 12v switched and constant power wires are sometimes backwards. Maybe?

 

It will be ok for a couple of weeks or so then loose presets