I'm just guessing here, but it wouldn't hurt to make sure that the EP500 power cord and DVD component video cables are as far apart as possible, and crossing at right angles if they have to be close. I don't think this is the problem though...
How is the AC wiring handled ? Everything on the same circuit ? 3-prong outlets with good grounds ? Is the Starchoice receiver on the same outlet as DVD player ? If not try swapping the power plugs and see what happens.
At first glance this sounds like a power problem... EP500 sucking lots of AC and making the ground on your DVD player jump up and down.
M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8
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