In the previous 128 test I got only 1 CTD at map change. Wrote it off as normal.
Yesterday, I got several. First was practically when I joined, still in the spawning screen. Second was in the middle of the round doing nothing in particular, not too many players in sight, no massive amounts of statics coming into view. Third was along with a mass disconnect when there were about 5 tickets left in a map. Fourth was again at map change, fifth in the middle of a map again just running along.
Also, the 128 mode seems to hate me, because it constantly keeps switching me away from the team all the time, even if I am in a fireteam, doing rather well, and am not the last to join. In 64 I rarely, if ever, get switched by the server.