Four episodes in this set contain a hidden audio commentary, in addition to the featured group commentary:
"Stark Raving Dad" (Disc 1)
"Lisa's Pony" (Disc 2)
"Bart the Lover" (Disc 3)
"Separate Vocations" (Disc 3)
To access these commentaries, do either of the following:
1) While the episode is playing, select audio track 5.
2) From the episode's "Special Features" menu, enter "10" with your remote. (This can be best achieved by using your "+10" button.) A hidden feature menu will pop up on the screen allowing you to access the commentary.
From Disc Three's main menu, enter "84763" with your remote. (After entering each digit, wait for the main menu to reload.) This will bring you to a set of Season 3 audio outtakes.
From Disc Four's "Special Features" menu, enter "742" with your remote. (After entering each dight, hit enter.) This will bring up a special sketch drawing. (Repeating this egg will cause different sketches to appear.)