I have a very strange case here. One of our customers have on ATA installed, with both ports configured exactly with the same configuration, except for the DN, which is different.
A fax is connected to the first port, and it works great, it receives and sends faxes.
Another fax is connected to the second port, but it doesn't receive or make calls.
When you call this fax, the call finishes after the first tone. Here you can see the debug:
*Feb 13 09:33:29.376: ISDN Se0/0/0:15 Q931: RX <- SETUP pd = 8 callref = 0x005B
Bearer Capability i = 0x8090A3
Standard = CCITT
Transfer Capability = Speech
Transfer Mode = Circuit
Transfer Rate = 64 kbit/s
Channel ID i = 0xA18382
Preferred, Channel 2
Calling Party Number i = 0x2183, '935555050'
Called Party Number i = 0xA1, '932720000'
*Feb 13 09:33:29.408: ISDN Se0/0/0:15 Q931: TX -> CALL_PROC pd = 8 callref = 0x805B
Channel ID i = 0xA98382
Exclusive, Channel 2
*Feb 13 09:33:29.408: ISDN Se0/0/0:15 Q931: TX -> ALERTING pd = 8 callref = 0x805B
Progress Ind i = 0x8088 - In-band info or appropriate now available
*Feb 13 09:33:31.732: ISDN Se0/0/0:15 Q931: TX -> DISCONNECT pd = 8 callref = 0x805B
Cause i = 0x80AF - Resource unavailable, unspecified
*Feb 13 09:33:31.756: ISDN Se0/0/0:15 Q931: RX <- RELEASE pd = 8 callref = 0x005B
*Feb 13 09:33:31.768: ISDN Se0/0/0:15 Q931: TX -> RELEASE_COMP pd = 8 callref = 0x805
You can see the cause of disconnection is "Resource unavailable, unspecified".
If you connect a phone to the same port which is failing and make a call, it is disconnected when you answer the other phone (for internal calls) or it is disconnected after one ring (for external calls)
What can be happening? physical problems with the ATA device?
Thanks in advance