I bought a MT II a couple weeks ago and it had problems with locking up occasionally, mainly just after writing files when stopping recording, but also sometimes mid-recording. I got two subsequent replacement units and had the same problem with both of them. I just got a fourth unit from a different vendor altogether and it has the same trouble. I have 2 completely different CF cards (Transcend and SanDisk) and even tried a super expensive one at my local camera shop but I get the same problem no matter which card I use also. Of course M-Audio support was no help at all. I have been surprised to look around the web and not find any mention of this problem. Do you guys really all have MT II units that don't lock up all the time?