I have had the same problems with my CD 500 for many years. I even had Meridian replace the CD drive and laser about two years ago (at a cost of �200), and the thing still skipped and refused to play some discs. Now that Meridian have stopped supporting this model, I took matters into my own hands and found that I could buy another replacement mechanism (Philips CDM 12.4) on eBay for as little as �10. Fitting it is not too difficult, if you know how to do a little delicate soldering.

This remedy worked, but here is the interesting thing: I unmounted the mechanism again to stick on the thin black metal cover (this is only cosmetic), and on re-assembly, found that the fault had returned. So I went through the process once more with the unit plugged in,checking at each stage to find out what was making the difference. It transpires that the fault occurred when I tightened the rearmost screws that attach the black plastic drawer, on which the mechanism is mounted, to the metal sliding tray. I even noticed very small sparks when the screws made contact. I also noticed that, when the fault was present, the drawer is sluggish to open, but when it is not, the drawer slides out smoothly.

So, here is my theory (which I leave others, with more time on their hands than I do, to investigate): the root cause of the fault is mechanical - when the housing is tightened onto the metal tray, it can distort it just enough to produce some slight misalignment or binding, so that the ejection motor has to labour and draws a high current. Somehow this leaves the tray at a different voltage, so that some power is being drained from the CD drive, giving it the symptoms of a prematurely weak laser. Remember that the CDM 12.4 is used in a multitude of other machines, without people complaining about skipping all of the time.

Anyway, if this is the cause of your problem, then my remedy would be to remove the two rearmost screws; I have had no skipping since I did this, and the drawer is quite secure enough without them. These are the small black phillips screws that you can see underneath the drawer when it is out. There are four of them, but you cannot get at the fourth, at the rear, unless you loosen the three torx screws that secure the lower edge of the front panel and prise the latter out by about 1/4". Good luck - I would be interested to know whether this works for you.