I was a bit of a naughty boy and managed to accrue one of them fancy global bounties that was introduced recently and was foolish enough to swap out some modules in my ship. Unbeknownst to me, the modules remain 'hot' even if you then clear your bounty. I'm unable to put the modules back on my ship now and it seems the only way to get rid of the 'hot' status is to pay an exorbitant fee (Just under 2mil credits for 7A modules and just under 1mil credits for 6A modules. Seems a bit steep for a 600cr bounty).