Phone Freezing Issue

So, we have narrowed down (we believe) an issue why some of our agent phones will freeze when they try to answer a call. It seems that if they are unlucky enough to try to answer a call when that call is answered by another tech, or sent to our voicemail blast. We solved the two agent answer at the same time with a round robin w\ memory setup, but we still have a couple of agents phones freeze if they try to answer the call, when that call is trying to go to voicemail, or the caller hangs up at the same time.

  1. Is this normal behavior? 2. If not, how do you solve the freezing issues in these cases? Would entering a delay or some other option work?

(Here is a screenshot of one such instance where a phone froze because the agent answered as it was going to the VMBlast group).

what kind of phones?

Oh sorry, Digium D50’s about 80 - 100 of them.

sorry can’t help on this one. we have very minimal experience with digium.