Bit of an older system here. 7200 MCP with expansion cabinet. 4.46. Analogue lines and mix of digital and analogue extensions.

On both types of extensions and on multiple lines, occasionally, a call will go silent. If the user puts the call on hold, or parks it and then retrieves the call, they can get the conversation back. Sometimes there drop has a beep before it drops, sometimes it is silent.

Wierd, no?

The alarm history doesn't show any issues at all.

Any ideas?