E39 changer woes

[dan101smith]

Having a mare with the cd changer in the 530.

It worked fine for ages, then one day decided to show "no discs" even though the magazine was in, was loaded with the same 4 discs it had played every day previously, and one tray of the magazine was clearly in engaged position.

Anyway, I took the changer out, took it apart, reset the tray in the magazine, refitted it and still the same problem.

So, a second hand (tested) changer was ordered. This arrived, and I fitted it. Initially I left the magazine empty, and when powered on the drive did the usual check of loading each tray in turn to check if there were discs. There weren't, and it went back to the unloaded positon - fine.

So, I then loaded some (different) discs in, and it just did exaxtly what the old one did - one tray engaged and "no discs" on the HU.

So, I'm wondering if the HU is not controlling trhe changer properly? It's the 16:9 nav unit.

Any thoughts on next steps? I'll be fitting the BMW aux socket at some point, but it'd be really handy to have the changer working too...