I've checked the forums, but I couldn't find a similar post.
I'm experiencing the following problem on our AP setup - We have a RB532 with an extra daughterboard (can't recall the model nr now). Regardless, this daughterboard (channel 2) on our AP, stops running.
Despite disabling and re-enabling it, it receives packets for a few seconds and then stops again. Up the yesterday, it was still working fine.