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8x8 Support

Top 10 Reasons Calls May Disconnect


The term disconnect here is defined as you are talking on an active call (aka you have not put it on hold, parked, in the process of picking up, etc) and the call ends. You no longer see the call on your display with the call timer incrementing. If you do see the call on your display with the timer incrementing, that means the call is still continuing and has lost audio, which is a different topic (but maybe related).


The below top ten are listed in order of probability (from most to least likely). Always refer to 8x8's X Series Technical Requirements for best practices. This covers both UC (Work) and CC (VCC) calls.

1. The Public IP has changed 

Where to look for a fix: Usually related to multi-path, load balancing, failover, redundancy actions of a router with 2 or more WAN ports or a SDWAN device.

2. The NAT Port changed

Where to look for a fix:

  • TCP timer is less than 300 - 700 seconds (TLS connections only, port 5443)
  • UDP timer is less than 300 seconds
  • Ensure all devices have a unique NAT Assignment (for example each device has a unique IP:Port combination)
  • General NAT assignment/session issue with Edge: When making corrections to timers, make sure you apply to ALL layer 2 or 3 devices as some networks may have multiple firewalls and access points in line.

3. The device has lost registration with 8x8

Where to look for a fix: See the suggestions for Reasons 1 and 2 above. 

4. Issues with SIP Signaling or Session Timers

Potentially, SIP signaling (such as Keep-Alive/ACK communication) is blocked, or Session Timers are interrupted on your network.

Where to look for a fix: Ensure over protective security practices are not causing the issue, such as DPI, SSL Decryption etc.

5. Incorrect Call Control

Where to look for a fix:

  • For Contact Center customers: Rather than attempting to use the call control (park, hold, transfer, etc) from your physical device or the 8x8 Work application, call control must be done from the Contact Center Agent Workspace interface. VCC should be set up where Work applications do not present call control features.
  • When the Work for Desktop application is set to Call Using Deskphone, you must use the desk phone for call control options.

6. Remote side disconnected unexpectedly

This may include cellular drops due to poor coverage (tunnels, building restrictions, network overload).

7. Wireless Headset disconnects

Where to look for a fix:

  • Check battery
  • Check within range
  • Update Firmware or OS on device

8. Loss of Internet

Where to look for a fix:

9. Loss of Power

Where to look for a fix: Restore Power

10. Carrier Issue

8x8 will manage communications in this situation and release notifications as appropriate via the 8x8 Status Page.

Getting Help from 8x8 Support

When reporting issues to 8x8 support, having the right details to share is KEY to assisting 8x8 in identifying the cause of the call drop. It is CRITICAL to report as soon as you can due to the length of time logs are available.

Important information to have available

  • If you have an open ticket provide the ticket number, or reference that there was an open ticket for this previously
  • What was the exact representation/experience when this happened
    • Example: I was on the call for 1 min talking and then the call dropped, caller called back and said they could not hear me.
    • Example: I was on the call for 45 seconds and then could not hear anything, eventually the call ended.
    • Example: Call was very choppy, very hard to understand, audio cutting in and out and then it was gone.
  • Were you on a hard phone, Work for desktop, or Work for Mobile
  • Were you In the office, at home, or "on the road"
  • Do you have more than 1 WAN link?
    • If yes, how is load balancing, load sharing, failover, SDWAN implemented?
  • Were you on WiFi or Hard Wired?
  • What was the time & date of the call along with the Caller ID (Inbound) or Number Dialed (Outbound) as well as your extension number
  • Approximately how many times has this happened to you previously, and does it happen to others in the organization

Network Utility and MOS Score are not usually necessary

It is important to note that the Network Utility or Network Assessment tool will provide little to no assistance in resolving this issue due to the tool is designed to identify issues in Setting up a call or registration issues not identifying issues of an ongoing call. Nor will the MOS score of the call/past calls in most cases, MOS is related to the RTP stream also known as "Voice Quality" For example the call was choppy. This information is always welcomed but may yield little help.

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