I've used TuxGuitar for a while now and it's good enough for a free product. However, I recently downloaded the most recent version and noticed that when I play what I've typed into the TAB the rhythm is ridiculously off. Simply put, the s/w does not play what I wrote with a nice steady uniform meter. It almost sounds like there's a bug in the programing. It I thought it was a person performing I'd give them an F. It's really that bad. Steady 16th notes seem to be playing as if they are galloping, with occasional n-tuples played fast then a pause.
I have heard about a function in Band in a Box called "humanize" that is supposed to introduce random deviations in tempo to mimic what someone thinks a human does when they play. Could that be at play in TuxGuitar? And if it is can it be turned off? I did not notice this in older editions but to be fair I usually use MuseScore, which plays scores correctly, and then use Tux for TAB in rare cases where I don't want to forget intricate fingering patterns I've worked out.