I just setup the spare unit in a window that gets a good signal. It appears to have the same problem, as you can see in the short log pasted below:
Jan 1 00:06:37 kb_unit1-10912c kern.warn klogd: client mode Group Message 2-2 done
Jan 1 00:11:37 kb_unit1-10912c kern.warn klogd: client mode Group Message 2-2 done
Since the distance to the ISP AP is only a few hundred feet power levels are set to lowest to avoid the units "shouting" at each other. Beacon is OFF, turbo OFF, IAPP is ON. Mode = B+G. AP is using B. More setup info on request.
Both 2112s appear to be setup the same, but one is on the roof and the other is currently in a window. Is there any setting in the 2112 that could cause this, or is the ISP AP the more likely culprit? Could the ISP AP be setup so that it re-nogotiates encryption every 5 minutes for security, or to disconnect inactive clients?
BTW, despite the error messages both 2112s are functional.