Car stereo issues

[Stevo143]

Hi I'm having problems with my aftermarket car stereo for some reason it works fine when I put the keys in the ignition but when I start the engine it goes really quiet but when I turn the steering wheel the sound goes normal then goes quiet again.

Car garage has checked battery and alternator at said they are fine.

I have Checked all wires behind the stereo and can't find a issue there.

I did recently have an issue with Broken wires in the back passenger doors which stoped the speakers and central locking working but I have fixed them.

Car is a 04 zafira

[littlebasher]

I've had similar in the past, with a broken speaker wire shorting to ground.

Going by your symptoms, best to start behind the steering column !

[Stevo143]

I have checked for broken cables and can't find any could I use a multimeter to check each speaker wire if so how please