[Retrotechie]

When it flashes bright upon initialisation, is the screen bright blue or red ? Or just bright white ? If it’s a particular, this would indicate a gun shorting on the CRT.
It’s possible there’s an issue on the PA board, though these are more fiddly to swap (worth checking the electrolytic capacitors of course).
The fly backs were generally reliable on these though there was a faulty batch on later serial numbers, which resulted in a distorted raster, rather than an overload issue. Unfortunately, all parts are long since discontinued and the factory closed in 2008.
The BVM-D24’s were the last of the grade 1 CRTs before Sony changed to lead free soldering with the ‘A’ series CRTs, and then it was LCD & OLED after that.

Good luck,
Retrotechie