This one is pretty weird.
Calling outbound from the UCM on a GXW2170 or DP750, if the call rings through to the recipients voicemail, the caller hears the voicemail greeting start, but then the call just dies.
Luckily, one of the numbers that this happens to is one of the users’ own cell phones, so I can test it. It happens every time this cell phone is called, but it’s also happening when users call out to their customers and they’re unable to leave a voice message.
If I call out to my own cell phone, I get my greeting and then I can leave a message.
If I call out to the client’s troublesome cell phone and he answers it, we have audio in both directions and the call does not die.
They are not reporting any difficulty on regular outbound calls where the recipient answers - only on some calls when they reach a voicemail box. Other voicemail boxes are fine.
The troublesome cell phone that we know of is a Verizon Wireless cell phone. My cell phone is T-Mobile. I suppose it’s possible that all of the problematic voicemail boxes are Verizon Wireless devices . . . but there’s no real way to know that.
It’s a UCM 6202 with firmware 18.104.22.168.