Should investigate and write a bug report for them (maybe even a fix).
If wait for the end of the default shmidusic on my main page and repeat playback couple of times (on my acer with 1gb it's three times) you'll discover that Firefox apparently takes (50 - x where x -> 0)% of CPU and music starts sounding really bad (like if someone moved audio jack).
Should investigate and write a bug report for them (maybe even a fix).
If wait for the end of the default shmidusic on my main page and repeat playback couple of times (on my acer with 1gb it's three times) you'll discover that Firefox apparently takes (50 - x where x -> 0)% of CPU and music starts sounding really bad (like if someone moved audio jack).
The issue is also obaudiously heard on the MIDI.js web site main page: http://mudcu.be/midi-js/