Yes, adjustment A.2.03 is Extra Ball Percent, with range from off to 35%. I would guess that cranking it up to 35% might increase the odds of seeing it in video mode, but add me to the list of people that can't recall seeing it lately. Although since I use the video mode strategy of straddling between lanes 1 and 2 and slightly nudging left and right to pass the cars, I might be oblivious to seeing EB in lane 3 - I'm too focused on 1 and 2. (Or missing out on lane 1 when straddling 2 and 3.)
EB in video mode might also be ROM-dependent. I'm playing with L-2.
Here's the text from the manual:
A.2 03 Extra Ball Percent
The operator chooses the percent of games that award an Extra Ball. The range of
this setting is Off, 1% through 35%. Note: If set to Off, the Random feature (Burn
Rubber) and the Video Mode awards zero Extra Balls, but the Skilled Extra Ball is
Post edited by yonkiman: added text from user manual