Sony PVM 20M4E, odd de-sync on certain frequencies

[LordBarker]

Hi all,

Got a few PVMs in my collection and all work without a hitch. Recently got a 20M4E and for the most part it;s superb. However when fed an odd refresh rate: think Midway games at 53/54mhz, the game runs but occasional the screen goes a bit weird like it de-syncs. This is momentary then it returns, but keeps doing it every few seconds. Everything else including consoles etc. is fine, wondering if there is some sort of issue with this that can be corrected as it's only with games that offer a refresh rate outside of 50 or 60hz.

Thanks.