Strange volume loss

[Reedorgansforever]

Hi everyone, it’s me with the Baldwin D-422 again. I have started to notice that during service playing, it’s as if the organ begins to get weaker as it’s played, to the point where it can barely support congregational singing. A pianist friend of mine played piano with me during the church’s Christmas Eve service last week, and things started off ok, but as the service progressed, I could no longer hear myself at all. We also played a piano and organ duet, and by that point, it was as if I wasn’t playing at all. What would cause this?? Is the EA-5 amp beginning to go?