Hi John,
I haven't tried with headphones, to be honest. It only affects the first track and after being switched on. My amplifier (a Denon AVR-X250-BT) auto-detects the input signal, which makes me think it's a signal delay, more than a B2b issue. If no-one else has the same issue, I'll put it down to the amplifier!
Thank you for your reply.
Christian