Digital Mica modems marked B (Bad) on 3600 platforms is a known issue. Usually that issue appears on the mica modems which are running old firmware and ios image. After some time of operation, the ios loose track of mica modems so it can't allocate it to imcoming calls. So is the reason ios will mark those modems BAD. Rebooting 3600 will fix the issue for a while but it will come back again later.
To fix this issue, First, make sure to use latest mica portware like 2.7.4.0 or 2.9.4.0 with any 12.2 ios. So let me know which ios you have with mica portware and also the output of command "show diag" from 3600.
