Super CD Rom2 crackling noise

[elartur77]

I got this system and at first it didnt worked at all, no power, I had to replace the power conector because it seems that the contact metal was bent inside the connector, after that it powered up and working, Hucard worked but no audio and CDs didnt worked at all...

So I did a complete recap and cleanning of the board, and now Hucard worked and has good audio, CD part worked but has long loading times and crackling audio.

I read somewhere thats because some dirty vias, I didnt see anything evident but still cleaned again, and now I dont know if it is worse  but still the audio is scratchy.

I already bought a new laser because it seems that the original isnt going to last longer, but I dont think it will solve the audio Issue..

Does someone know how to fix the audio?

Here is a video to hear how it sounds.

Thanks.

[Keith Courage]

Whoah, that sounds really weird. I've heard scratchy audio from a worn out lens before but this sound isn't the same.

Have you tried making any lens adjustments?

[elartur77]

Have you tried making any lens adjustments?

Hello Keith..

Yes I tried to adjust the lens, before that the disk didnt loaded, after messing with the pots now they load but still have long loading times even sometimes crashing.. this drives me to think that I need a new laser..

About the sound, the HUcard part has clear sound, this only happens with CDs, the Video looks great but the audio with Music, Games, Backups CDs, all has this noise..

I dont think is a bad laser, Im more inclined to think that maybe is a bad capacitor or some other component from the audio part...

I just found a guide in this site for laser calibration, so Im going to follow it and hope this helps..

If someone has another idea please let me know..

Thanks

[NightWolve]

TheSteve wants a test to make sure that just Redbook PCM wave audio is playing. Load a regular music CD, play any track to hear what happens.

[elartur77]

TheSteve wants a test to make sure that just Redbook PCM wave audio is playing. Load a regular music CD, play any track to hear what happens.

Hi there.

I understand, here is a new video playing a music CD it has over 40 tracks hope this helps..

Thanks a lot.

[NightWolve]

OK, Steve watched the video and has some advice I'm forwarding back:

1) Check the output pins on all op-amps, should be around 4V. If this is the problem, it could be the "LR clock trace." He's seen that once, so implies it's a rare failure.

2) If not, a capacitor could be bad or it's an issue with the bias resistors or even cap juice on board (meaning, you should've washed/dried the whole motherboard to really clean leaked capacitance fluid off before soldering on the new caps...).

Good luck!

[elartur77]

Thank you..

I did a little more cleaning yesterday, I found some covered bias and after that it really helped and improved the audio, I still have noise but not as bad as in the video. So maybe that's the problem, proper cleaning, point 2 from Steve's recommendations. When I cleaned the board I only used cotton swabs and IPA, I understand that this way it does not clean deeply, but the truth is I do not feel comfortable cleaning it with water, I have never done it and the quality of the tap water here is not very good, if I do it I would have to do it with bottled water.

Well, next time Ill try washing the board first, for now Im going to keep cleaning more with IPA..

Thank you very much, I will follow these recommendations.

[Tak-MK]

From my experience, cleaning the area surrounding the power area helps with the issue of not having sound for the first seconds/minutes of booting up, because of a trace that goes all the way from there to the sound daughterboard, middle pin of the seven that there are if I'm not mistaken, but I don't know if it's the same issue as you have.

[elartur77]

Yeah, I knew about that trace and try to clean deeply but still didnt help, I think I have to clean deep in other areas where that trace goes..anyway Im waiting for the new laser because still Im having issues with long load times and skipping tracks..

Thanks

[elartur77]

Update..
The new laser arrived, I already replaced and now read a little better no skipping but the loading times are still very long.

Tested with original Cd music..loads ok and plays ok no skipping but still some noise, not as bad as before but still there.

Tested with backup CD music..it loads and plays ok, no skipping but lot of crackling noises.

Tested with original SuperCD.. It loads ok but every time that needs to load is a loooong wait but after that the game goes like normal, never crash or something like that.. and still crackling noise..

Tested with original CD game.. Same as SuperCD games, goes ok but long loading times and some crackling noises.

Tested with backup SuperCD games.. Try to load the game the please wait screen goes to black and it seems to load but just stays there trying to load but nothing, no crashing nothing..

So does someone knows what does this behavior means?.. why I'm having long load times even with the new laser?

[Tak-MK]

Definitely no idea... sadly I fixed only two of them and their issue was mostly the low audio level at start.

[elartur77]

Definitely no idea... sadly I fixed only two of them and their issue was mostly the low audio level at start.

 I don't know what's going on, maybe I did a bad job with the capacitors.