Bosso:
I leave my 950 on continously (not in standby) and it gets warm, but not too hot to touch, like a power amp might be. It is dissapating 45 watts of power (from the spec sheet) so I would make sense that it would get warm. Having a DVD playing on repeat I would think would make no difference in the heat, but I've never tried that either. I leave it on continously because:

1) I'm basically lazy.

2) If it _is_ going to sound better by being left on, then I'm covered.

3) There's the stability thing. Electronics generally like being left on continously, avoiding thermal cycling. The circuits get nice and stable, especially things like the DACs, and as a result, the longevity is enhanced, and that can't hurt the sound either.

4) I'm basically lazy.