Somehow, after installing new, updated sound roms, I installed S2 backwards. Yes, I'm an idiot. I orientated the chip and dropped it and picked it back up reversed. On startup, no sound and I unplugged the machine after about 10 seconds. The S2 was very hot, I assume I fried it. I replaced the updated sound chips I likely just fried with the prior working originals. Now I have no sound and a sound board interface issue error and no led light lit on the AV board. Fuses are good. Suggestions as what to repair? Any chance that S2 is still good? Would it fry all of the sound chips? The game has no other errors or play issues but plays soundless. I found no open fuses on any boards.
I reseated the cables, double checked to ensure the OEM sound roms had all their legs in and were in the proper slot and order.

I know I'm being punished by the pinball gods for updating sound chips that I likely couldn't tell the difference with the new ones anyway. But i couldn't help myself. Now I need help. The AV board shows no signs of burns or charring. Anyone else made this mistake?

Yes, I pulled the plug and grabbed the rom only to find it very hot. I removed it, cooled it down, and put it in correctly, and have no sound. So I removed all 4 sound roms, replaced them with the prior working ones, and I have the error "sound board interface error".

Can anyone tell me what gets fried if you put S2 sound rom in backwards? I notice R44 on the board is very warm while others are not. Thats a 1.8 ohm 5 watt vertical resister. Should it be hot to the touch?

The LED 501 is not lit on the audio visual board, what do I test to troubleshoot it?

Ok, the Junk Yard is all repaired and working now. After I installed the original sound roms back in the AV board, I failed once again to notice all of the bottom legs on one chip were outside the socket. I know, geez. I'm having my glasses checked, I must need a new script for them.

Thanks to all who tried to help me with this. It was really appreciated. Hopefully this post will help another one day and I sure am glad I didn't have to pony up for the $2995 for a AV board!!