Intermittent Distortion on start up

I haven't had this problem , and I don't have the same kit, but to help you diagnose, does this only happen when you play CD? If you play from another source eg disc or tune,  is that ok? If you only have CD, can you try plugging into a different input on the preamp? Does the distortion move? Your CD5 is also left on all the time? but you get the distortion every time you play a CD after a gap from the last? How long does the gap need to be for you to get distortion again?

Also I imagine you are using a din to din interconnect between the CD and the preamp. I don't know the units but if you can replace that temporarily with a cheap RCA phono to phono lead then you could easily identify if the distortion is in the CD player or the amplifier.

Those are probably enough questions for the moment! It might be a capacitor issue, but there are lots of other things that could cause it. You are going to need to send something back for repair, but the aim must be to find which is faulty unit so you don't have to send the whole lot back.

best

David

It sounds like more of a CD5 problem than an amp or pre-amp problem. Especially if it happens every time when you first start playing a CD in the CD5.

If it was an amp issue, I would think it would distort continuously in the problem channel. The fact that it happens every time you start a CD gives me reason to believe that is where the problem lies.

If it happens that with every CD (rather than with every CD playing session) it always distorts for a few minutes at the start on one channel then I agree with Badlands.