I have a TDM410 with 4 FXO cards on a FreePBX server and cannot detect if the caller hangs during voicemail.
I have two analogue lines, one giving 500ms open-loop-disconnect and the other 800ms. There is no polarity-switching, just the voltage drops to zero. This is followed by a continuous 400Hz tone.
I have the configuration set to UK,
hanguponpolarityswitch = yes,
Enabled Busy Detect.
I cannot find any info about defining a busypattern for disconnect followed by continuous tone or any settings for minimum / maximum CPC.
As a work-arround I’ve set maximum VM message to 60 secs and require a key-press to record so I can stop going to VM if they hang up first.
I can see this is a common problem but cannot find any answers.