I recently bought a PC Engine DUO-R and it has some audio problems. I've got 3 CD games and no (PCE) hu card games at the moment so I'm not sure whether the problem is only with CD games or if it also applies to hu card games.
Anyways on games with "cinematic intros" (YS 1&2, Far East of Eden 2) the sound skips a lot during the intro. There's weird noises, no sound at all, then I hear the sound clearly for 1 or 2 seconds then it goes mute again and so on, it barely works. But once I start playing the games there really aren't any problems with the sound quality. But in YS 1&2 and Wonderboy III the music suddenly just stops playing at times.
In YS everything works fine once I start the game. No problem with sound effects or anything like that, and music plays completely normally. I can go to buildings, talk to people etc with out any audio problems. But once I get outside of the starting village and attack an enemy, the music just suddenly stops. It wont start playing again untill I go outside of the screen to another area, after that it starts playing again and plays as long as I dont attack any enemies.
In Wonderboy III there is a very similiar problem, it just doesn't seem to follow any kind of pattern. I start the game, everything works fine. No problem with sound effects or any of that stuff. Music plays normally. Then suddenly the music stops playing and the game will become (music wise, sound effects still work) mute untill I finish the stage. I can play some stages from start to finish with music playing normally, in some stages the music dies mid-level, in some levels music is mute untill I encounter a boss but after that it starts working. It's really weird.
I live in Europe and I'm using a step down converter with the console. I got the console from hit-Japan on ebay and it came with the original power supply and AV cable. Atleast I think it's the original AV cable. I've tried using two different step down converters (PAL->USA and PAL->Japan) and a C64/SMS/Mega Drive 1/Genesis 1 compatible AV cable but it didn't have any effect on the problem.
I dont have the tool required for opening the console at the moment so I sadly can't take any pictures of the insides. Based on what I just told you guys, do you think that the capacitors have gone bad or could there be another explanation?