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New Member

Trouble Faxing with VG248

Sometimes I experience problems sending faxes with our fax machine over the vg248. These are connected with the latest image 1.2.1 to call manager ver 3.22 with PRI's. I get a lot of COMM errors on the fax. I just upgraded the firmware today of the VG because I read about the recent improvements to faxing. This did not help. If I take the fax and hook it up to a regular pots line and fax to the number that was giving me problems before, the fax goes through. Does anyone have any recommended settings for the fax options in the VG or a solution?

New Member

Re: Trouble Faxing with VG248

We also had a lot of problems with faxing throught the VG248 when we first went live. We have around 14 fax machines running throught 2 seperate VG248's. After playing around with the settings alot it has been working great for 10 months.

You already did the first step - VG248 Software version 1.2(1)

DSP Firmware 3.6(20x)

Here are the setting

Port Specific:

Fax Relay Enabled

Fax Relay ECM Disabled

Fax Relay NSF Overide with 000000

Passthrough mode : Default:Automatic

Advanced General Setting:

Fax Relay Payload Size: Default 20

Fax Relay Max Speed Default 14400bps

Fax Relay Playout Delay Default 300

Hope this helps.


New Member

Re: Trouble Faxing with VG248

Thanks I will try some of these settings. I disabled Fax Relay in the interim on one port and it seems to have helped a lot. Although I am not sure of the long term affect of doing this. What is fax relay? I have read a lot of posts in the meantime which suggest turning that off. I will try some of your settings and re-enable it...

New Member

Re: Trouble Faxing with VG248

I found the main problem with faxing from a VG248 connected fax, was the analogue levels. In Australia we have a number we can send faxes to, and by return fax it tells you the quality of the fax.

The problem when running fax relay was the output level of the fax was too high ( apparantly this is the most common problem with faxes), with fax relay the gains cannot be adjusted ( input/output settings on the analogue port of the VG248 have no effect as the Fax relay encoding takes no notice of these settings).

To overcome this problem Fax relay has to be disabled on the VG248 port to force Fax passthru, which does take into account the levels from the analogue port. you will find your faxes should then be ok.


New Member

Re: Trouble Faxing with VG248

Hi Richard,

What is the number we can send faxes to in Australia ?So we can find out the quality.