We have had many of our Yealink phones become unusable until they are rebooted. I am requesting an engineer to help us find out why 20 or so of our phones are doing this. The latest happened yesterday. The phones touch screen would take 20 - 30 seconds to respond to user input and the dial tone would take 30 seconds to come on once the handset or speaker option was used.

Once the phone has rebooted, the issue is resolved. We have had several phones have the issue more than once. Some only happened once. Has anyone had this issue or think of a way to resolve it?