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Client Troubleshooting

Jonathan edited this page Aug 6, 2020 · 54 revisions

Home > Using Jamulus > Troubleshooting FAQ

We are currently compiling a list of common problems and solutions.

You all sound OK, but it's difficult to keep together

If at all possible, DO NOT listen to your direct signal. Make sure you are listening as much as you can to the sound of your own instrument/voice coming back from the server. This signal has you and your playing partners mixed together in sync, and will be the signal that your bandmates are hearing too. So listening to that means you will be in sync with each other (assuming you all have reasonably low latency). Note that if one or more musicians are not following this rule, they will slow down as they play or sing.

You can test whether you are hearing your signal correctly by doing the following:

  1. Get your audio into your computer.
  2. Use an audio recording application (such as Audacity) on your computer to record that input and check it's OK.
  3. Make sure that if you mute your audio input inside the recording application, you can't hear yourself.
  4. Close the recording application and run Jamulus. You should still not hear yourself.
  5. Connect to a server and play something. Now you should hear yourself with the delay from the server.

If you are still having problems, try asking on the hardware forum. Exactly how you avoid listening to your direct signal will depend on your individual setup - your sound interface, mixing desk, headphone connection point, etc. For example, some audio interfaces have "monitor" buttons (turn these off), or similar options.

Be aware that while listening to the server's signal will ensure you will be in sync with other musicians, you may also experience problems if your overall latency (indicated by the "Delay" light in Jamulus) is not green or at least yellow most of the time. Consult the software manual to understand how to adjust your setup to help with this.

Getting frustrated with software channels, audio routing, sample rates and more?

It's usually far easier and more reliable to have a mixing desk to connect your kit (instruments, mic, recorder etc.) and then send a simple stereo signal to your sound interface (be sure to listen to the resulting sound from the Jamulus server via your computer though!). The huge variety of possible hardware, software and instrument combinations means that setting up your sound card to work with your particular configuration can otherwise get complicated very fast.

Buffer LEDs suddenly going red, outages, jittering, weird sounds?

The CPU in your computer may be having issues. Try not to have anything competing with Jamulus (like Zoom Meetings or Facebook live streams) on your machine. Or at least quit them while you're playing. Prevent things like virus scanners doing scans, or software updates happening, etc. Be aware that the reverb setting in Jamulus also uses more CPU the more reverb you have.

Getting blasted by somebody joining your jam with feedback or noise?

You can set your "New Client Level" to a low value (eg 10), or set the musicians you are playing with to "Solo" state (in the mixer panel on the right side). That way, either new entrants will be very quiet, or you won't hear them at all.

Can't see the server you want to join?

First check that you have the right genre server selected in your Connect Setup window. But sometimes network issues mean your client won't list all the available servers. If you know the name of the server you want to join, you can look up its IP address here. Enter the IP address in the "Server Name/Address" field in the Connect Setup window to connect to it.

Not seeing a list of servers at all?

In the UK (and possibly other regions/routers) the Virgin Media Cable Internet Modem setting can cause an issue. "Block Fragmented IP Packets" should not be checked. For other routers/ISP, also try turning off SPI (Stateful Packet Inspection) and if that fixes it, you can make a judgment about whether to leave that off or not.

In some cases, it may be your ISP that is blocking your use of Jamulus. See the note on the server troubleshooting page about "Nobody can connect to my server"

Trouble using Garageband (or other DAW) with Jamulus?

See this forum discussion

Can't work out your mic settings?

When using a microphone while playing your other instrument, you can use a stereo audio input signal in your settings where one channel is connected to the instrument and the other channel is connected to a microphone signal. On the microphone channel an optional reverberation effect can be applied.


For anything else, please search or post on the Discussion Forums