I'm having the same issues with an Elvira and the Party Monsters. Callouts are deafining, and the background noise is driving me insane. Can you tell me specifically what changes you made to the system 11B sound board, as (at least on mine) there's no potentiometer on the sound board. Thanks!
Quoted from calico1997:
Yes. It was it has been the same issue for me and basically the same fix. The sound was intolerable and probably on the verge of damaging some hardware. Difference is that I put the pot on the board instead of in the wire. The sound is not perfect but decent now. I previously tested this Rottendog board in Swords of Fury which is Sys 11B. Same damn problem with the digitized sounds. Probably as you pointed out, one of the resistors in the schematic are not what's on the board and Rottendog missed this. What gets me is they have not supported customer complaints and several suppliers now refuse to even sell the 11A-11B daughter board system from Rottendog. I think the 11C games are okay though, as they don't use the daughter board.
But I was also told by someone this week that Rottendog just sold their business to someone else. Perhaps that entity will make improvements. There's just a ton of System 11 games out there and many burned up boards. We need alternatives and the Kohaut boards are not being made as of January 2017. : (