Cisco 9971 Intercom issue with firmware sip9971.9-4-1-9

[SteveBallantyne]

I was working on setting up an Intercom feature this week between a 7965G and a 9971. In my testing environment I used two 7965G devices and it worked fine. But repeating the same configuration with my 9971 didn't work. When calling with the intercom, I got the "this call cannot be completed" message (which is usually a CSS issue). After playing with the configuration for a few wasteful hours ... I tried rolling back the firmware to sip9971.9-3-2SR1-1 and surprise, it works fine.

I opened an issue with TAC, but they are trying to make me install the latest device package. I would rather not suffer through another cluster wide reboot, when I already have a work-around. Seems like they should have a testing environment for this sort of thing. Plus - I am only one version behind on my device package and the firmware for the 9971 is *unchanged*. They are arguing that there could still be configuration options that may have been updated. Fair point - but again - I don't want to be their testing environment.

So I am throwing this topic out there for two purposes:
1) Has anyone else had this problem, or has a 9971 they they could test with?
2) Perhaps someone else with this issue will stumble onto this topic and find my roll-back workaround useful