[dansalvato]

Could be, I’m not familiar with how the sync is generated. But have you seen them tested with SCART, or just VGA? VGA syncs fine for me, but the noise in the video signal is just too much of a drawback.

Would you be able to help determine, from a technical standpoint, what might be causing this kind of noise/jitter? To get a good video sample of the noise, I deliberately offset the H. samplerate by a few values and sharpened the video output: https://www.youtube.com/watch?v=a-PrBT-P2w0

You can see that the vertical bars are so jagged that there is no vertical slice of the screen that is free of noise. So even with a perfect samplerate and sampling phase, bits of the screen are in constant horizontal jitter. Here it is with a perfect samplerate and phase, again sharpened to better display the noise: https://www.youtube.com/watch?v=YTDmXDWRyMw

Applying a video LPF of 9MHz (EDTV) eliminates most of this noise, with the exception of the largest spikes.

[dansalvato]

Understood, thanks for providing that info. I dug up a DB23<->VGA cable I forgot I had and tried VGA input. It syncs at RGBHV, but it’s perfectly stable and works on every power-on. The downside is that video LPF doesn’t work with VGA RGBHV/RGBS, and I was previously using it to filter out some of the noise coming in. So as of now, it’s a small hit to the image clarity in exchange for hassle-free syncing. I think I can safely blame the noise on the Amiga hardware and not my settings. Here’s hoping someone eventually designs a digital RGB output for Amiga, as the video chip outputs digital RGB which is then converted to analog using an onboard circuit.

[dansalvato]

Sure thing, here’s the standard display:
AV1: RGBS 263p
15.72KHz 59.79Hz (sometimes 59.75Hz or 59.82Hz at random)

Second display, from what I assume is the INFO button as I’m using a non-standard remote:
Prof.0 1600×240
263p* 451305 (sometimes 451306 or 451307)

H-PLL adjustments had no effect, nor did any other setting seem to in the sync options. By this way, this occurs both on my custom profile and a profile with fully default settings.

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