I have around 10 voip phones which have been working without fault but about 4 weeks ago, they started dropping calls and sometimes when people pickup the call, there is no one there. Also, the indicators on the phones which indicate people are available/on the phone are not updating in a timely manner. The voip provider is blaming this on a change in our network but there has been no changes to our knowledge. Ive been running wireshark for the past 24 hrs in an effort to find out what could be causing this but I have no idea what I need to look for in the wireshark logs.
Any suggestions on how best to tackle this type of issue?