It means that Java Sound Api, couldn’t load a MIDI device. We know that this problem occurs with some sound cards on GNULinux, but we coludn’t determinate why...
The first thing to try is to close all the application that might be using sound output and restarting TuxGuitar after. If it doesn’t work try to change Tools→Settings→Sound→Sequencer to “TuxGuitar Sequencer”.
We could find a possible solution to this problem, but we don’t know if it works on all the soundcards The solution consist in two steps:
Load snd_seq module
Use alsa-oss as wrapper
To verify if the snd_seq module is already loaded , you must open a console and execute the following command:
This command will show a list of the modules loades on the Kernel, on wich should be snd_seq. If the file isn’t on the list, you can load it executing the following command (as root):
You can also load this module at GNULinux boot, by adding snd_seq on /etc/modules
This steps consist on execute TuxGuitar with alsa-oss as wrapper:
To do this, you must have installed the package alsa-oss on your sistem, it can be downloaded from here