Resolved an unexpected issue with the sound install
After trying various other solutions, I decided to give it my best shot by attaching the LGB 95004 to the brown and white leads off the power pick up wires. After putting it all back together, I tested it on my main line, powered by a LGB 10 amp Jumbo transformer - everything worked as advertised! It turns out my one amp transformer on my test bench had insufficient power for everything in the LGB 24430 engine: 2 motors, 12 lights, two pantograph motors, the charging of the LGB 65011 power capacitor, and the sound unit! (This is all on an analog layout.)
The instruction sheet states you need at least a one amp transformer to run the sound box. I thought "check, I'm good there!" Even after reading the entire instructions 5 times I didn't think the instructions were probally written for a single motor engine...
Problem solved! I thought I would share it in case someone else runs into this same issue!