We had a similar problem here also, including affecting analog calls too. The problem ended up being interoffice trunks on Ameritech's network between two local end offices. 2 T-1s out of 7 were taking errors. Since signalling occurs on the ends of the calls and SS7 is on these trunks, the call wouldn't drop. It took us 3 months to get them to find the problem. Jeff u>I have a community that is within our local calling scope that has u>always required the ISDN connections be set for 56K on the client u>equipment. If we set the client for 64K it would connect but no data u>would pass on the line (both ends of the connection think there is a u>valid connection, this really confuses the telco). In the last month u>or so I have begun having problems where the circuits will not pass u>data for various length periods of time, then will begin working. The u>routers (multiple sites) do not drop and redial the calls, they are u>the online the whole time (I have watched both the leds and system u>monitors at our end and the customer end). The telco is convinced that u>if there is really a connection problem the ISDN connection would u>immediately drop, but that is not my experience in this case. u>Any ideas? u>Mark Thornton u>San Marcos Internet, Inc. u>512-393-5300 CMPQwk 1.42 9999 - To unsubscribe to usr-tc, send an email to "majordomo@xmission.com" with "unsubscribe usr-tc" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message.