Steering Wheel Controls (Radio)

[acrowot]

I have just installed a Sony CDX-CA750X and Autoleads adapter for steering wheel controls in my Xantia. The steering wheel controls work most of the time but sometimes strange things happen when I use them, the latest being when pressing volume up, the volume continues to inrease until full volume is reached (I am a little deaf now). The only way to stop the noise is to switch off the radio as all controls are now inoperative both on the wheel and radio.Other strange things happen like pressing mute sometimes brings up the soun menu. I have emailed Autoleads and they say the later Sony radios are a problem with the Autoleads adapter and suggest I try to sourcs an older Sony or Kenwood/Pioneer.Has anyone else had this problem and resolved it.
1996Xantia TDSX