I have a regular T-1 circuit provided by Verizon. I recently installed a 670 with this T in service when the T goes down it will not sync back up and return to service. I hae removed all programming in 670 and reprogrammed, changed out T-1 card anf CPU and cabinet and even added an Adtran csu. the Provider says he has no problem and even changed his pairs service box. Also talked with Toshiba Tech support and they say they never had this problem before. I am at a loss. except for changing customer over to copper.

What software level is the ctx on?

the latest off ftp site, was on 227 now 236

How often does the T1 go down? Double check correct protocol and line encoding. What slot do you have the T1 in? The manual shows that it cannot be in slot 7 except for the base cabinet. In the System Data program 105 fb 21, do you have the primary clock set?