4610SW IP Phone Lock up when put into Aux

[Furface64]

We have issues with phones locking up in Aux mode. The agents place themselves in Aux mode for various reasons and when they try to take themselves out of Aux the phone is non-responsive. YET, CMS sees them as in service and starts sending calls to them. There is no way to answer these calls as the phones are not responding.

We have this in three locations. Two are remote locations connected by frames and the third is on the same network.

This happens 10-20 times a day. The only way we've found around this is to reboot the phone and then all is right.

Anyone have any ideas what to do?

Firmware on phones is 2.8

Thanks