My Sony 1252 during the first 30 minutes from start up will make this crackling sound around the tubes and the tubes flash with horizontal lines on the screen (this flashing is on all three tubes because the screen color of the bright lines is mostly white).

I am feeding the projector only 480p from the crescendo transcoder into RGB. I do not think this has anything to do with the transcoder I have running it for 6 months now with no problems until recently.

After the major horizontal flashing calms down the projector still has a symptom like the scan lines are not lining up horizontally then they will settle in. I am afraid the flashing is going to cause some kind of tube burn.

Anybody knows what the cause is?

Thanks

Hv arcing. Open the set to see where it's coming from. You might need an HV lead or two to be repalced on the tubes, or the HV flyback/splitter might be leaky.