Heat is your enemy. The TV heat goes left and right some, and up a lot. The receiver has lots of heat, worse than most TVs. The DVD player isn't a big heat producer, and I think it's stealing away "cool" space you can use.
Put your hands on that wood. Is it warm? Where?
Part of the space is okay for discs, but not too close. You cannot use the whole area on the left of the TV, but you can use most of it.
It's overall just really a bad place to store discs. Under a TV is better, in a single unit like that.
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