I have a Quadro M26x with about 20 analog phones connected via the RJ21 connector. They all suddenly stopped working at the same time. I can call the FXS extensions from an IP phone and it will ring on my handset and go to VM. All IP phones are working just fine. The call log shows that the call went to the extension and then to VM as normal. The fault light on the Quadro is NOT lit. I see some curious references to the FXS lines in the "messages" log (daemon.warn seems bad to me):

Sep 1 12:41:05 NHHM-Phone daemon.warn klogd: ^ITYPE: 20480 - "24FXS"
Sep 1 12:41:05 NHHM-Phone daemon.warn klogd: ^ISN: 000000000000000000000000
Sep 1 12:41:05 NHHM-Phone daemon.warn klogd: ^IVERSION: 1.1.0/0 patches:00000000
Sep 1 12:41:05 NHHM-Phone daemon.warn klogd: detected LC 24FXS module

And

Sep 1 12:41:05 NHHM-Phone daemon.warn klogd: VE880: Stuffed 2 FXS are detected.
Sep 1 12:41:05 NHHM-Phone daemon.warn klogd: VE880: LC 24 FXS are detected.

These are the only two references to FXS in the whole "messages" log. I have unplugged/re-plugged both ends of the RJ21, rebooted the device many times as well as fully power-cycled it.

The RJ11 on the front of the device works (port 2..port 1 doesn't seem to).

Is this a hardware failure on the FXS module?