This happen 1 out of 10 times. When we get an incoming call from someone using a google voice number and they typed the extension that they want to get transfer to the person get routed to another number voicemail. We tried it our self in-house and we also get the same thing using google voice. Can it be possible that if someone is calling us with a VoIP system our inter-tel can't recognize the tone of the numbers pressed?

Thanks,

Absolutely. Depending on the specific hardware installed and software version, you may be able to adjust DTMF timers and frequency twist to compensate.

Go to Voice Processor / Timers and Limits / DTMF Detection Information and press F1 for help.

Be sure to document all existing values before making any changes, so you can revert back if necessary.

Thank you DND ON for your replied. Right now everything is set to default. Do you know if the DTMF timers and the frequency twist have to be higher or lower to work better?

Thanks.

Try increasing the digit detect timers one step, then test. Changing the digit delay settings never seemed to do anything.

Increasing the twist settings makes digit detection more sensitive, decreasing them makes digit detection less sensitive.

Try increasing twist settings by two steps, then test.

Increased sensitivity might cause talk-off, where voice is mistaken for DTMF. Increasing digit timers should correct that.

We have lots of trouble with Google Voice into anything. We just figure it is Google Voice.