I had the 4006 yesterday twice in dynamis-D, which had never happened before, even with some extra speed, however yesterday my speed was not being manipulated. 4006 might be finding something more then just speed now?
some things you might not expect like no-interrupt lua and fast follow can present as position hacking to the server, especially if in a high latency environment, so it's possible even if you didn't strictly have a speedhack enabled you triggered it with something like that