Increase duration of DTMF on Digium PRI gateways

Anybody know if there is a way to increase duration of DTMF tones on Digium PRI gateways (G200)?

I have problems with DTMF going through my gateways not being accepted on the other end, sometimes I need to enter twice.

DId you try changing the dtmf mode?

I think, from GUI, you can not change the [quote=“avayax, post:1, topic:37485”]
duration of DTMF tones
[/quote]