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VG248 and 6608, modem noise/garbage

Have a VG248 using a 6608 for PSTN connectivity and on dialup console modem (terminal sessions) the modem connects but there are garbage characters on terminal session now and then and the connection sometimes drops. These are 2400 and 9600 baud modem connections they are doing to devices they need to dial into. They have tried multiple modem makes/models and the modems work fine when a plain old POTS line is used (not VoIP).

Am running latest code on VG248 and on CCM 4.0(2)a Sr2b

The T1s on the 6608 are clean and no visible issues; we have no other issues on voice calls. FAX's are fine to.

Using legacy mode on 6608 and VG248 right now.

New Member

Re: VG248 and 6608, modem noise/garbage

I have seen this issue also. I have not had the time to investigate it though.. Same HW setup. Using T1-CAS and PRI connections to the PSTN.


Re: VG248 and 6608, modem noise/garbage

We use that same setup (CCM 4.1(3)SR3) with no problems. Are you configuring the VG ports for modem passthrough ecan disabled? Does a show port voice active X/X confirm passthrough mode?

Re: VG248 and 6608, modem noise/garbage

Have tried that and some other settings. This is a VG248 also, so is menu driven - no show commands to type.

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