[SOLVED] Hifiberry Amp2 click on playback start / stop

[new_bloke]

Does the lack of response mean that no one else is experiencing this issue? Are there any others out there using the AMP2? If so, I'd be really grateful to hear whether you are hearing a pop when playback starts / ends? I guess it's possible I've got a duff board or something...
Any suggestions of things to try would be great too. Big thanks to Tim and team for this amazing system - it's super!