Prelude 1200 playback issue - video included, any help appreciated!

[rvo_nl]

Hi guys. I am about to give up on this wonderful piece of hardware. I have tried anything I could think of. Different versions of AHI. Different versions of Workbench, including a plain 3.1 one with no CyberGraphX. A different accelerator board. No accelerator board. No Indivision. No PCMCIA. Different mp3 files. Different audio programs (play16, amigaamp, digibooster).

important edit: the lower playback frequency I select, the longer it takes for the issue to appear. It eventually happens at 28khz, too: a terrible hissing / white noise and a crashing or unresponsive system. Sometimes after 2 seconds, sometimes after half a minute or so, as you can see in the below video. There must be an explanation for this! I am starting to think it's my a1200 motherboard, but why? Any other ideas?

Electronic gurus? Audio experts? This is my last call for help. I desperately need it to complete this project.

Here is the video of the issue: http://nl.tinypic.com/r/2i085so/8

[rvo_nl]

Hi, Im still fighting with my Prelude..
 
 But, after many hours of frustration, I have noticed one very important thing. This issue only seems to occur when the Prelude (or some other component) is.. COLD. After the machine has been on for half an hour or so, playback is fine, no distortion, no lockup etc.
 
 So, what does this tell? Bad contact somewhere? Can that be solved?
 
 Could it be the power to my motherboard? The power connector has some issues, when I press it, the machine crashes. Something is loose there, but can that influence audio playback?
 
 Any thoughts or other ideas? Where do I start?

BTW, this Prelude is one amazing card, I cannot believe the quality of sound output!

[Brian]

I'd say it sound like you're on to something.
First of all fix the powerconnection issue, it's not that uncommon for the powerplug on the motherboard to be worn out or solderpoints to become lose over time so resolder or replace the plug. Also as the issue only occure when the system is cold I'd check for a bad soldering on the prelude, I'd also try with a different motherboard if possible.

[rvo_nl]

thanks. I will look into that at some point this year.

[Oldsmobile_Mike]

Have you had your system recapped yet? I know caps issues sometimes manifest themselves as audio trouble.

Also random question, any difference if you try changing to a screenmode like DblNTSC or DblPAL?

[rvo_nl]

a recap sounds good. I might do that if I can find someone here who can do that for me. have not tried with PAL modes I think, but I will try tomorrow, good one.

[rvo_nl]

same issue on a PAL screen. strange enough, even when the machine is warm the sound output will eventually crash. after a reboot, its okay again. restarting winamp doesnt work. its as if memory gets corrupted. Im no hardware guy, but is there memory on the prelude that serves as a buffer or something?

[paul1981]

Like Brian said, you really need to fix your intermittent power issue first as that's a likely cause of system wide instability!
 A re-cap wouldn't be a bad idea too as Mike mentioned.
 You can't really say that the Prelude is faulty until those issues are dealt with first. 2nd option would be to buy a known working spare motherboard. Try Amibay or ebay for the motherboard.

[rvo_nl]

yep, thats the plan. reporting back later thanks!

[delshay]

There are no issues with prelude sound card when I last used it here. This card also works under OS4.0 but I never tested it under OS4.1.

If you are having problems with this card it can only be driver issues provided there is no hardware fault(s).

I can't remember I will have have to take another look to be shure but i think a "digital out" is on the card but is not connected.

[rvo_nl]

thanks delshay, good to hear from another prelude user.

[rvo_nl]

Like Brian said, you really need to fix your intermittent power issue first as that's a likely cause of system wide instability!
 A re-cap wouldn't be a bad idea too as Mike mentioned.
 You can't really say that the Prelude is faulty until those issues are dealt with first. 2nd option would be to buy a known working spare motherboard. Try Amibay or ebay for the motherboard.

so, got the power issue sorted and have a recapped motherboard now. problem gone. thanks for suggesting this.