Random DTMF Tones during voice calls on Spark Wireless Broadband

Spark have started selling Wireless Broadband with a voice connection to clients in small towns

which dont have fibre.

An interesting issue seems to happen where you get random DTMF Tones every so often during a call.

Its the party that is not using the voip over wireless broadband that hears the DTMF tone ( or beep if you want to call it that )

Its fairly random how often it happens but does seem to be when the female at the other end is talking.

Doing a quick google on it I see it's a phenomenon called "talk-off".

To put it simply, random tonal qualities in regular speech will trigger the DTMF generator in theTA to produce a 'touch-tone'. It's been said female voices (or voices with more 'highs') do it more then male voices.

Does anyone have a suggestion how one can speak to the right person at Spark to see if they can adjust the

minimum and maximum duration thresholds for the DTMF side of things as I suspect the main support desk is just going to go Huh?