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You can't do that on a per category basis, the logic to support categories for this is just too complicated due to the fact that you can have multiple categories for a post, as well as nested categories.
You can control if the player appears or not on a per podcast Channel basis. Podcast Channels is a feature you can turn on under "Advanced Options" in PowerPress. Podcast Channels add unique feeds tied to specific podcast episode entry boxes, it gives you the flexibility to have multiple media files per post, as well as separate feeds for those episodes. Channels can be setup to be password protected, and with the help of other plugins they can provide secure (or some call premium) rss feeds.
To control on a per episode basis what is displayed, go to PowerPress settings> Basic Settings, for the first section "episode entry box settings", select the options you want for the player and links options.