To Keith,
Doesn't it remind you of a similar thread at another forum ?
To Greg,
You did not tell us what SSL you have ( E or G ), and the year of manufacture.
Anyway, I would suggest you to implement this mod to ALL of the Dynamics card of your console.
On the output of the 78L12 : solder a diode ( typ. 1N4148) with the Cathode on the output of the regulator, and the Anode to ground.
On the output of the 79L12 : also solder a diode, but wire it with the Anode on the output of the regulator, and the Cathode to ground.
Wire the diodes on the copper side of the card, between the pins of the regulators.
Afterwards, when you'll power on/off a channel, the Dynamics card will always power on, 100% reliable.
Without the diodes you need to be lucky if you have all the Dynamics cards of the channels working after a console powered on.....
Also, take this opportunity to replace the electrolytic cap ( 10