Hi, I too have this problem on iPad, iPhone and Control:PC however Control:15 is fine. I've rebooted all systems and even tried running the core on the C15 and MD600 to no avail. Oddly it does not do it for all albums, but I'm yet to discover any pattern to it.

It�s most annoying and could trick the folk into deleting what they might think are genuine duplicates.

Regards,
Carl

EDIT 2012-11-07 Control:15 Explorer - Album by Artist is affected frown

861v6+ID40, HD621, 8000.2, 7200HC, 7200.2, SKYQ Silver, PS3, PDP-LX6090, QNAP TS870-Pro (8*6TB), Roon, iPadAir2.
[In Reserve] C15, MD600 (2*3TB), TwinStore RM (2*2TB)