I have the same problem. Citroen say that it is a faulty head unit. As the head unit is no longer available I have had to leave it with a radio specialist to see if he can find the problem. May need a new tuner which is "not cheap".
I will update with his findings.
Dave Evans
February 2009
I have the same problem. However, it seems it is quite common in early C5s where water leaks in under the aerial mounting. It needs to be taken out, cleaned and reseated and sealed. About 2hrs work for a mechanic. Probably expensive, then!
Jeremy
February 2009
The radio is easy to remove, their is a flap either side that pivots at the top so use a small screwdriver to ease the flap up at the bottom. Underneath each side is a single star headed screw, once removed the radio slides out (no code to worry about). The reason I know this is because my radio keeps messing about, the volume in effect goes very quiet. This happens when it gets warm, the CD is fine. This maybe a similar problem but I am still investigating.
Paul Farley
March 2008
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