I have fax machines connected to a VG224 FXS gateway going out to the telco via a PRI on our 2811 Router. Both gateways are connected to callmanager 7 via MGCP.
I am having issues where faxes to certain remote fax machines do not go through and I get the error on the fax machine of poor line quality. Faxes to the same remote number through an analog line work fine.
I opened a TAC case and they have told me that the new fax machines SuperG3 mode is not supported and I must disable SuperG3 or ECM on every fax machine.
This makes absolutely no sense to me that Cisco will not support a feature on Fax machines that virtually all new fax machines have.
Has anyone else run into this issue and did you find a fix other than disabling SuperG3 ECM on your fax machines? I would think there would be some way to set my gateways to adjust ECM SuperG3 rather than have to manually program each fax machine (100+ fax machines).