-- Redirecting Zap/3-1 to fax extension
  == Spawn extension (inbound, fax, 0) exited non-zero on 'Zap/3-1'
    -- Executing SetVar("Zap/3-1", "FAXFILE=/var/spool/asterisk/fax/.tif") in new stack
    -- Executing SetVar("Zap/3-1", "FAXFILENOEXT=/var/spool/asterisk/fax/") in new stack
    -- Executing RxFAX("Zap/3-1", "/var/spool/asterisk/fax/.tif") in new stack
Nov 14 14:08:14 WARNING[4145]: channel.c:2326 set_format: Unable to find a codec translation path from unknown to unknown
Nov 14 14:08:14 WARNING[4145]: app_rxfax.c:309 rxfax_exec: Unable to restore read format on 'Zap/3-1'
Nov 14 14:08:14 WARNING[4145]: channel.c:2326 set_format: Unable to find a codec translation path from unknown to unknown
Nov 14 14:08:14 WARNING[4145]: app_rxfax.c:315 rxfax_exec: Unable to restore write format on 'Zap/3-1'