SDLC intermittent connect issue

I have a customer who has an SDLC dialup into an AS400 (NSRouter/WinSDLC).
In 1999 it worked fine (pgmr dialup situation).  Now it will connect the
first time no problem and then will not connect again until the line and
ctrl unit are varied off and on again.  We have swapped modems so I don't
think that is it.

The msg is:

Line SDLC01 failed; probable modem problem or local hardware problem

ERR code 

x54001490; 

44001624-either CD or rcd line RLSD has dropped while receiving data from
the remote system
or the DSR signal has dropped.

CPA596D; machine detected; SRC B01056F1; device type 2720; orig ref code
56F1; DSR dropped on modem interface.

Any help?  TIA.

Jerry


Jerry Draper, Trilobyte Software Systems, since 1976
Specializing in connecting PC's, Windows, MAC's, and LAN's to the AS/400
Representing Synapse, Apple, IBM, UDS, Nlynx, MI, Perle, Netsoft, etc.
(415) 457-3431; (415) 258-1658fax; jdraper@wco.com
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