Caliper or handbreak issue v70 p2

[ben5732]

Quick question before I ship it off the the garage! Phase 2 v70 T5 ex plod slight brake squeeking when I pull off after putting handbrake on and a rumble at 60-70 for a minute or two then it stops and all is normal till I stop and put the handbrake on again. If I don't put the handbrake on and leave it in gear it seems fine. Handbrake sticking? Also Is there a quick and easy DIY solution? Cheers.