lineGenerateTone failed; "The operation is not supported by the underlying service provider" #35
Description
Error code is 0xFFFFFFFF80000049
This happens if I try to generate a custom tone. Is this a limitation of the modem, or a problem with how I'm using the function? I can dial a number normally when placing a call, but can't dial numbers once the call is running.
EDIT: Same for lineGenerateDigits! I need to be able to send DTMF tones during a call (e.g. "press 1 to..." continue in menus), so how am I supposed to do this?
The modem reports "InteractiveVoice | DataModem" as its capabilities. Are more capabilities needed to produce custom tones?