I may have to join all the tracks from one 'album' together to achieve seamless playback...
Exactly -- I find these issues don't happen with every track on my playback from USB sticks, only with some cases, and usually problems with PCM files not DSD
I've had DCS upgrade to all the latest firmware and that didn't solve the problem ... one reason I stick with CDs and SACDs for my digital, plus I always find that playback from USB sounds a bit "off", a bit lifeless