Three beeps then call drops/disconnects

[maxrev]

I've been researching and troubleshooting an issue of calls randomly dropping at one of my client's office. The feedback that I've received from users at this office is that they hear three beeps in short succession on their deskphone (Fanvil X5S, X6, Yealink T42S) before their call suddenly disconnects.

The main question I have at the moment is what are the potential causes of this beeping sound? This may help me troubleshoot the issue while I collect tshark packets. I've asked my VOIP provider if this sound is coming from their end however they confirmed that they do not send any disconnect beeping sounds.

 

[ovax]

As i understood that beeps appear when connection is lost, and application tries to switch gsm/WiFi connection

 

[JohnS_3CX]

Hi,

Some additional info would help narrow it down:

- When making external calls only? or are internal also affected?
- What is the setup? please follow the Information to provide when requesting help guide
https://www.3cx.com/community/threads/information-to-provide-when-requesting-help.67558/

 

[JohnS_3CX]

As i understood that beeps appear when connection is lost, and application tries to switch gsm/WiFi connection

This may not apply, the OP said it is happening in deskphones, not the app