Hi there,

In my application I am using Mitel's MT8880, DTMF tranceiver.

It can detect DTMF tones from a telephone installed on the same line. But during a call progress it does not respond to the DTMF tones. Though the DTMF tones are well audible on the telephone set on the same receiving line.

Is it the gain problem ??

I am using it in single ended configuration.

Help..........

Simon