Common Issues
What browser should I use to access virtual classes?
Google Chrome is the preferred browser for the virtual class feature. Other browsers are supported, but you may encounter certain features that do not work as expected.
Why do I keep getting bumped off Znanja?
If you are suddenly bumped out of a virtual class, check your bandwidth speed. (More information on bandwidth can be found below.)
Another way to get bumped out of a class is by clicking a link on the left-hand sidebar menu of the LMS. When in a virtual class, avoid using any of the commands of this menu.
Should I have my camera on all the time?
As more cameras are turned on, more bandwidth is needed for both users and the system. Cameras should only be used when necessary if bandwidth speed is an issue.
When I enter the virtual class, my screen is black. What causes this?
Check your bandwidth speed.
What do I do when everything freezes? When the webcam video keeps spinning?
Check your bandwidth speed.
Bandwidth and Devices
What bandwidth speed do I need?
For audio and video connection, you need 10+ MB. For audio-only, you need 2+ MB.
How do I measure the bandwidth of my device?
You can do a speed test at: https://www.speedtest.net.
What generation of iPads/tablets will give users the best experience?
The newer the unit, the better the performance. You can speed up your iPad by consulting the following instructions: https://www.macworld.co.uk/how-to/ipad/speed-ipad-3632709/.
You should also ensure there is storage space remaining on the device to allow for processing. You can check your device’s available space by going to Settings > General > iPad Storage.
How do I update my iPad?
Go to Settings > General > Software Update. If one is available, you can press to Download and Install.
Which data networks can support virtual classes?
We recommend 4G LTI for best results. At minimum, 3G can be used to access audio, presentation content, and screen sharing.
Audio and Video
My mic and camera are not working.
Ensure that the webpage has been granted permission to use the mic and camera. Click the Padlock icon to the left of the webpage URL, and set both permissions to allow.
Also check that your audio device (mic, camera, headset, etc.) is turned on, receiving power, unmuted, and selected as the default device on your computer or device.
I can hear everything, but my mic is off.
Look at your audio icon at the bottom of the window. If you see a mic icon, you should be able to speak. Check that your device is turned on and receiving power.
If you see a headset icon, you are in listen-only mode. Click on the headset icon and select Join Audio. Then select Speak + Listen and complete the echo test.
What type of earphones will I need?
In most cases, a cell phone headphone or earbuds will suffice.
Glossary of Error Messages
1001: WebSocket disconnected
- The WebSocket had connected successfully and has now disconnected
- Possible causes: loss of internet connection, or Nginx (server) restarting
1002: Could not make a WebSocket connection
- The initial WebSocket connection was unsuccessful
- Possible causes: Firewall blocking WS protocol, or the server is down or improperly configured
1003: Browser version not supported
- Browser doesn’t implement the necessary WebRTC API methods
- Possible cause: out of date browser
1004: Failure on call
- The call was attempted, but failed
- For a full list of causes refer here: http://sipjs.com/api/0.6.0/causes/
1005: Call ended unexpectedly
- The call was successful, but ended without the user requesting to end the session
- Possible Cause: unknown
1006: Call timed out
- The library took too long to try and connect the call
- Possible causes: Previously caused by Firefox 33-beta on Mac. Error has not been reproduced since the release of Firefox 34
1007: ICE negotiation failed
- The browser and FreeSWITCH try to negotiate ports to use to stream the media and that negotiation failed
- Possible causes: NAT is blocking the connection or Firewall is blocking the UDP connection/ports
1008: Call transfer failed
- A timeout while waiting for FreeSWITCH to transfer from the echo test to the real conference.
- Possible causes: This might be caused by a misconfiguration in FreeSWITCH, or there might be a media error and the DTMF command to transfer didn’t go through
1009: Could not fetch STUN/TURN server information
- This indicates a network interruption or a system bug. Can also be caused by using an unsupported new client or older server combination.
1010: ICE negotiation timeout
- After the call is accepted the client’s browser and the server try and negotiate a path for the audio data. In some network setups this negotiation takes an abnormally long time to fail, and this timeout is set to avoid the client getting stuck.