Some modems can't connect on particular lines

USB Devices
1

I don’t know if this has anything to do with the card, but I’ve about given up trying to figure this out. I’ve got some modems that cannot connect to my Citrix box dialling into the RAS 4 modem card. The weird part is that they only have problems when connecting in to the 800 number, which routes to a local number Hunt group. If they dial the local number, they have no problem. When they dial the 800 number, what happens is that it tries to connect, but never completes the handshake, but keeps going. I’ve tried setting the Digi board modem speed lower, and am using the 5.0.314 drivers. Again, the problem only happens on the 800 numbers, the modems connect to the same hardware via the local number fine. The phone company says there is nothing wrong with the 800. One thing I know is that the 800 line and the local line are owned by different carriers. Our phone system is Cisco IP based.

Any ideas?
Thanks

2

It sounds like the phone lines of the 800 number might have more noise or impedance than the direct lines. Our RAS modems conform to the specifications of a standard telephone line. Sometimes lines coming from a PBX or other non-POST line are not quite within this spec.

Try the following init string and see if this helps:
AT&FX0\V1\N3~V7=10S95=45%C0+MS=11,1,300,33600