I get this kind of messages several a day and they always repeat if trying to dial the same number again. In other words, while calling other numbers is still successful, calling this same number for 3, 4, 5, 10 times doesn’t help. I believe the operator hears the message “All circuits are busy” and the call doesn’t go through.
It is a small office, 3 extensions on one trunk. Sometimes there are 2-3 concurrent calls through the trunk, but most of the times it’s the only call, so the circuits are not overloaded. The other calls are going out and coming in just fine.
Incident happend 07.02.2019. 15:06.
Your [XXXXXXXXXX] tried to dial number YYYYYYYYYY.
Call could not be established on channel SIP/101-00003d14.
What can cause this problem?