Thanks to all for your kind attempts to help.

I've tried most things suggested to restore my missing albums. However, there is a new development which is making things very difficult. I can no longer access Sooloos with my PC, Netbook or Android tablet.

Control:PC doesn't connect nor does the Control:Web. I've checked out the IP addresses for my C15 and also TwinStore and my router correctly identifies them at the appropriate IP addresses. I'm totally flummoxed.

Looks like I'll be dragging all the boxes of CD's out of my loft and resurrecting my trusty all Sugden Masterclass Player!!

Any ideas?

C15, QNAP TS-453A, Synthesis A100T Tube amp with onboard DAC, Triangle Antal Anniversary Edition