Modded DC with distorted sound, already tried most common solutions, help!

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Seroczynski
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Modded DC with distorted sound, already tried most common solutions, help!

Post by Seroczynski »

Hi guys, I've been searching all over for someone who is able to push me in the right direction. No luck so far, and then I came across this board. Hopefully someone here will be able to identify the problem I am having.

I live in Europe but started working on a NTSC-U Japanese Dreamcast. Replaced the stock fan with a Noctua fan, installed a rechargeable battery, PicoPSU, GDEmu clone from China and a DCHDMI.

There were some issues with my GDEmu clone where some games wouldn't properly work. Crazy Taxi had problems with sound not working and textures not loading in time or not at all. I've replaced the oscillator crystal but somehow managed to break the entire thing so I've replaced it with another GDEmu, which has the proper crystal installed from the get-go.

Now when I start my Dreamcast, I am getting distorted sound over analogue and no sound at all over HDMI. The video is great, both through HDMI and analogue. No errors show up in the DCHDMI test.
  • I've already sanded down the PSU connector and tried with both the PicoPSU and an original Dreamcast PSU.
  • Measured voltages at the PSU connector, seems to be fine.
  • All the DCHDMI connections have been checked with a multimeter after installation and there were no shorts or loose connections.
  • I've also tried putting the original GD-ROM back in. Distorted sound is still an issue.
  • Tried different TV's
Here's a few pictures of my Dreamcast: https://imgur.com/a/QuGhh1Y

I'm not sure what else the issue might be. Should I go back and look at my DCHDMI Flex cable installation? This was working fine with the previous GDEmu I had installed, but that one had other issues.

I really want to get started on my games with this DCHDMI modded console. Please help!
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fafadou
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Re: Modded DC with distorted sound, already tried most common solutions, help!

Post by fafadou »

What are the green wire ?
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Seroczynski
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Re: Modded DC with distorted sound, already tried most common solutions, help!

Post by Seroczynski »

fafadou wrote:What are the green wire ?
Those are soldered wires for "Step 5 - Gamepad & Reset Wires" as covered by the official DCHDMI installation guide, source: http://www.dansprojects.com/dchdmi_install.html
DCDigital Dreamcast (PAL) + GDEmu
ChloeIsFab
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Re: Modded DC with distorted sound, already tried most common solutions, help!

Post by ChloeIsFab »

Can I ask, did you ever fix/find out the cause? I have the same issue exactly :(
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Seroczynski
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Re: Modded DC with distorted sound, already tried most common solutions, help!

Post by Seroczynski »

ChloeIsFab wrote:Can I ask, did you ever fix/find out the cause? I have the same issue exactly :(
I haven't. I've redone the DCHDMI installation and triple-checked all connections. Even when using regular composite out and the original GD-ROM I get these strange results, so I figured it must be something wrong with something else on the motherboard. But that's as far as my capabilities go.
DCDigital Dreamcast (PAL) + GDEmu
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