Requirements and best practices for interpreters



We recommend a recent computer, preferably high-end or at least mid-range with a fast processor and sufficient memory (eg. Intel i7 with 16GB RAM) and a dedicated sound card and graphic card. Insufficient CPU or memory may result in audio distortions and packet loss. Sometimes, this will be heard immediately. On other computers, it may cause the audio quality to gradually deteriorate.


The operating system doesn’t matter. It should only be able to run a recent version of Mozilla Firefox (make sure to install the latest update). We strongly recommend using Firefox !

Even though Google Chrome fully supports WebRTC and should also work, we recommend using Firefox for various reasons:

  • Using Chrome may result in poor audio quality and may cause audio quality to deteriorate over time (especially on budget computers).
  • We use Firefox ourselves for testing, not Chrome.
  • Firefox lets interpreters select their microphone when connecting to a language room. Chrome doesn’t, which may result in an interpreter being connected with the wrong microphone.
  • Google Chrome is more commonly used for everyday browsing. There is a higher chance of add-ons being installed that could affect performance.

Only if for some reason a translator can’t use Firefox, you should consider using Google Chrome.


We strongly recommend using a professional or high-end headset with noise cancelling. Cheap headsets are often the cause of audio distortions. A second headset should be available in case there are any issues.


The room from which remote interpretation is done should be as quiet as possible and acoustically suitable. When you talk or clap there shouldn’t be an echo or a reverberation. Ideally, you should find a small room with a low ceiling, a thick carpet on the floor, no windows and sound absorbing panels (you can get the same effect by covering the walls with thick curtains, blankets or carpets).

Internet Connection

Translators should have a wired ethernet connection! Even a good wireless connection may still cause a lot of audio distortion. A good quality cable (Cat 6 recommended) and connector are also important.

They should have a bandwidth of at least 5 Mbps up and 5 Mbps down. The time for packets to travel from their computer to our servers should preferably be below 50 milliseconds . If packets arrive too late, parts of your translation will be dropped or distorted. To check this, go to and click on the Change Server link. Next, type ‘I3D’ in the popup dialog and select ‘Rotterdam –’. Finally, press the GO button and wait until all tests are completed.

1. Click on the Change Server link

2. Type ‘I3D’ in the popup dialog and select ‘Rotterdam –’

3. Press the GO button and wait until all tests are completed

  • The PING value contains the time for packets to travel to our server.
  • The Download Mbps value should be higher than 5 Mbps, otherwise you may experience difficulties in watching the original video+audio stream.
  • The Upload Mbps value should be more than 5 Mbps, otherwise some of your audio packets may be dropped.

Note that these values are indications: good connections with less bandwidth or a longer packet travel time may also result in sufficient audio quality. But in that case you should definitely do plenty of testing.

Best Practices

Make sure the latest version of Firefox is installed

Do this before you start testing. Then go to the translator room and check if you can connect to video, audio and chat.

* the OpenH264 video codec (offered by Cisco Systems, Inc) should be enabled in the Firefox plug-ins. This is the case by default. If you can’t see the video in Firefox (black screen) this plug-in is probably not enabled. Try enabling it, or do a fresh install of Firefox.

** if you are unable to use Firefox and you have a high-end computer, you can try to use Google Chrome (after thorough testing).

Restart your computer and close all other applications

To make sure your computer is stable, restart it before translating. When you’re ready to start, close all unnecessary applications to prevent them from using your processor, memory or internet connection. Make sure the Operating System is not allowed to start or download automatic upgrades.

Use an ethernet cable to connect to the internet

Even a good wireless connection may result in audio distortion. To be sure, you could turn WiFi off on your computer (it may still use WiFi, even if an ethernet cable is plugged in).

Ensure that the sound from your microphone AND from the video stream goes through your headset

Make sure your headset is set as your computer’s default audio input and output setting. If the sound of the video stream is heard through your speakers, it will cause an audio loop and lead to interference.

Test extensively

Make sure to test beforehand with a stream that has comparable audio settings. While you’re testing, the event manager should watch the stream and help you to set the volume of your microphone.

Make sure your microphone is set correctly and speak with sufficient volume

Configure your microphone correctly, so it produces enough volume. Also don’t speak too quietly, the audio codec will have a harder time distinguishing your speech from anomalies. This will cause your speech to be erroneously corrected.

Mute your sound when another interpreter is speaking in the same language room

If multiple interpreters alternate, we recommend strongly pressing the mute button while another interpreter is speaking. Even if you make little or no sound, your microphone may still transmit ambient sounds or cause jitter. This will result in audio glitches.

Reconnect if a connection problem persists

If a problem (eg local network issue) occurs during the event, the audio of your translation will restore itself in most cases. If it doesn’t, you should quickly reconnect (press the disconnect button and then connect again).

More info about T@H