Color classic with LC550 motherboard -- sound issue

[cyelvington]

Greetings,

I have a color classic that is upgraded with an LC550 motherboard. My problem is that some of my games do not produce sound. The motherboard and analog board are fully recapped. Startup chime and alert sounds are loud and clear. Problem is, I think, that it's trying to output stereo when the CC only has mono audio. I can't change to mono in the sound control panel as it is greyed out. I think the computer thinks it's an LC550 and thus it's expecting to be able to make stereo sound. Is there any way I can force it to output mono audio? Games like Glider and Crystal Quest have no sound, but Stellar 7 has perfect audio. Any suggestions would be much appreciated.

 

[Fizzbinn]

I have a CC with a LC520 motherboard, I hadn’t noticed any sound issues but haven’t tried those games. Does the audio sound okay in the problem games using the rear headphone jack?

 

[cyelvington]

I just tested it with headphones. Same thing-- some games have sound, some don't. With Glider in particular, it flashes the menu bar when you adjust the volume, as if the sound is muted. So it's acting like it's muted rather than playing no sound at all. I run the same version on an SE/30 and sound is fine. I wonder if the motherboard might have leftover cap goop on it, and if so, would dishwashing it or scrubbing it with alcohol help.

 

[Fizzbinn]

What specific version of Glider are you using? I can pull my “CC+” out and test (I think the 25 vs. 33Mhz speed is they only real difference). Could be cap goo, I used a lot of flux remover (IPA plus solvents) and dental brushes on mine after recapping. 
 

Have you ever tried “Apple Personal Diagnostics”. It can do a sound checks, runs through, mono and stereo tests as I recall. I usually run it in a loop after a recap (just on logic board tests) for a while to make sure the board looks good, the system doesn’t crash. 

 

[cyelvington]

It's Glider 4.06 (the latest 68k version.) I wasn't aware of Apple Personal Diagnostics, but the board looks like it might have cap goop on it still and it feels a little sticky in places. I guess I'll pull it and give it a good scrub with a toothbrush and 91% alcohol and see if it helps.

 

[MJ313]

I just gave Glider 4.06 a try in my CC (w 550 board) and even though Sound is set to Stereo (Mono greyed out), the sound in the game worked fine.