I get blue static noise in the image and crackling audio only on matrix input 4, far worse with unshielded HDMI cables(missing 2 5 8 11).
Strange thing is it seems 100% fine with a good thick shielded cable and mini HDMI adapter, 0 noise. But if I use a thin HDMI to mini HDMI cable that has all 20 wires and shielding I get the noise.
This only happens on channel 4 though, other channels are fine with the Wiidual and unshielded or cheap shielded cable.
It doesn't matter if I wiggle the cables, twist them in a coil, nothing changes or gets worse so the connections are solid.
And I can put any other HDMI system I have on channel 4 with any cables and it runs fine.
PS1,3,4 Gamecube, MiSTer all display fine channel 4. All cables direct to monitor run fine.
This kind of points towards both channel 4 AND the Wiidual being at fault.
Like they are both on the edge of too much interference and when combined with a crappy cable show this fault?
An under spec filter on 4? A poor connection on a shielding pin on the Wiidual?
It clears up slightly if I put the RGB mode to limited on the WiiDual.
I remember vaguely someone had me remove a diode from a the HDMI port in a Wiidual install once for compatibility sake but couldn't find any more info on it.
Honestly, If I hadn't decided to put the Wii on that channel with a crap cable id never of found this problem and should probably just switch channels but I worry either the Wiidual will damage another channel or channel 4 will damage a system or output channel.
A little video of the issue. Recording was done with a HDMI cable that was missing the shielding wires 2 5 8 11 to easily show this issue.(thanks Ebay)
I had the audio channel off as it was pretty loud crackling when the speakers decided to do it.
https://www.youtube.com/watch?v=TwAuL1UeJm8
The first few components of channel 4s input are
PN520/TPD12S520 - Single-Chip HDMI Receiver Port Protection and Interface Device
MAX3815 - TMDS Digital Video Equalizer for DVI/HDMI Cables
24AA16/24LC16B - EEPROM
LT1097 - Op Amp
