I assume you have not tried other games. Anyway, Samurai Showdown 1 and 2 do not have sound in Neo4All betas 3 or 4, however the games sound great in Neo4All beta 2, and they still play at a really good speed. I think this is just a bug that appeared in beta 3, and was carried over to beta 4. It'll likely be fixed in the next release.
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