Williams Alco PA Sound Issue...

You might want to check the wiring. I had a Williams SD45 which had the horn going off with being requested. This was strictly a conventional setup. I found a wire that was close to one of the flywheels was making contact with the flywheel. It had done this enough that the insulation had worn away, and when contact was made the horn would sound.

That's not all that unusual for older sound boards and running through the TIU.  I haven't bothered to track it down, but I just hook up my old 1033 for testing those and the problem goes away.

I simply find those older Ott sound systems to be a bit stubborn at times.  My Willams PAs sometimes have sound, sometimes they don't.  Never took the time to figure it out and they since have been on the deadline having been replaced by newer spec PAs.  They are still great runners however.

On the flip side my Williams GG1 from that era never fails to produce decent sound. 

Thank you all for the replies.  

GG1 4877-I thought that looked like an OTT board, but didn't know that Williams used them.  Thank you for that info as well!