All theoretical questions aside for now.
While I agree that it makes no sense, sometimes we gotta start eliminating possibilities.
Was that orange tint there before you moved the speakers near the TV?
Does that orange tint go away when that speaker is moved away from the TV and the TV is turned off and on?
Could there be anything else magnetic in nature recently placed near the TV itself?
Well, the good news is that that narrows it down quite a bit.
But, the bad news is that it points to a problem with the TV itself. Generally, the effects of stray magnetic fields on picture tubes are corrected on power up by automatic degaussing circuits built in virtually any modern set. The fact that your set refuses to clear up makes me think it might be time for a service call or, if it's old enough to warrant it, replacemen.