I'm trying to get Tuxguitar to play a tab. Player>Start does read the tab, but no sound coming out. Xporting to a mid file and playing through timidity does work, though.
Based on these guidelines, I did
$sudo apt-get install tuxguitar-alsa. It then does appear in the list of plugins of Tuxguitar, but still no sound. Also shown below, Tools>Settings>Sound
Linux Mint 19.3 TuxGuitar 1.2