Back in December 2012 I posted a few times on this thread about 3 Audiolab CDQ's in a row that had start up and other problems.
After having so many problems I built a mains DC filter about 4 months ago from designs on the internet. A few large electrolytic capacitors and a heavy duty bridge rectifier. Since then the cdq has failed to start only a couple of times and then would always start on the second attempt, I cannot categorically say that the mains dc filter is responsible for the improvement in the running of the cdq but... with the Plinius amplifier and cdq both on the same mains block and dc filter (with ATC SCM35 speakers), the sound improvement was very noticeable, fainter sounds brought forward in the mix, greater separation of instruments, less noise, less hum on transformers, awesome!
If this entry has piqued your interest, don't even think about building a mains DC filter unless you have a lot of electronics building experience ... MAINS VOLTAGES! and has rather unconventional circuitry, two electrolytics back to back so that only AC passes.
Are there any other newer threads for the Audiolab CD/CDQ? last entry here in January.