Speakers off after new install...

[Terabyt3]

Got bored of the standard CD player in my Megane and went out and spent £200 on a Sony with Bluetooth in (main selling point as I drive long distances) The thing is after installing it I've noticed only my front door speakers are on. Meaning the tweeters on the dash and the rears are off. I have changed no wiring just simply plugged in and played. Any suggestions or anyone already had this problem?

[dougieCC]

Have you checked balance/fade etc, also is the rear channel output set correctly, i dont know much re stereo's but would try this first.

Alan