Upgrades/ New Shit in Norwich

^Could be anything. It's probably your bb/crank arms/chainring bolts, but it could be anything. Try loosening off, cleaning, greasing, and re-tightening everything from the top down. Saddle, seatpost, stem, chainring bolts, crank arms. Then if it still persists, whip the cranks off and do the same to the bottom bracket - assuming it's just a sealed unit you can make sure it's done up nice and tight on the fixed and the free side, as the bearings won't seize. If it still happens it might be because the frame hasn't been chased and faced, but I'd bet some money it'll be something simple from the top of the list that Matt's just forgotten to get up to torque.

Cheers Alex, I think I'll whip it into him to get checked out