Red MIL, but scanner reads AUM Fault
 

Still having a little 'fun' with the XC70. I've got the red triangle on, but the only things that came up on the scanner were 6D0F which was a 'child lock' relay, (fixed) AUM 48FD & 49FD which the scanner lists as Control Module faulty installation, and CEM 1A59 which the scanner lists as Communication AUM Control Module, both listed as Permanent Fault.

The original stereo system had been untidily replaced with an aftermarket unit, I bought a second hand 'original' unit and installed it. It is working, but I have noticed that sometimes it will switch to CD from FM Radio with out warning.

Clearing the DTC's makes no difference, they immediately return on switching on the ignition.

Anyone got any ideas as to what I can do to match the Stereo to the car?
Thanks