Question

Are pokemon with the ability soundproof immune to perish song?

Answer 1

>After 3 turns, all Pokémon that were on the field when Perish Song was used will faint unless they switch out. Perish Song does not affect Pokémon with the ability Soundproof. If a Pokémon switches out with Baton Pass, Perish Song will still be in effect on the Pokémon switched in, even if it has the ability Soundproof. -Bulbepedia

So no, Soundproof does not affect Perish Song.
Hope This Helped :D
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D®.F!@me

Comments

First you wrote that they were, and then you said they weren't, please verify.

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better? just read the part under the summary.