Stereo problems

[Pegasus64]

Hi all I am having problems with my sound system the quality of sound from rear speakers are terrible very distorted and on front drivers side is so quite and timmy have tried altering balance etc still the same so only got sound from front passenger side is this common would it be the head unit or speakers if I fitted a after market one would I need a facial or cable converter
Any suggestions please
Regards Simon

 

[clk320x]

Aftermarket , you will need a CONNECTS2 steering interface to keep the steering controls around £30, with a patch lead for the brand of stereo your fitting (around £5-8) , an aerial adaptor (around £2 depending where you get it) , and a fascia / radio cage fitting kit. Altogether around £75 normally