I tried the two files you attached and they played fine for me also (tried 5 times no errors)
>java -Djava.library.path=lib/windows-amd64-cp lib/xuggle-xuggler-noarch-5.4.jar com.xuggle.xuggler.demos.DecodeAndPlayAudio SND0(mega).AT3
>java -Djava.library.path=lib/windows-x86 lib/xuggle-xuggler-noarch-5.4.jar com.xuggle.xuggler.demos.DecodeAndPlayAudio SND0(mega).AT3
theme song plays. (same with SND0(3rd).AT3)
Serio >
did castlevania work on xuggle 3.4? I'm thinking that might be mono.
>java -Djava.library.path=lib/windows-amd64-cp lib/xuggle-xuggler-noarch-5.4.jar com.xuggle.xuggler.demos.DecodeAndPlayAudio SND0(mega).AT3
>java -Djava.library.path=lib/windows-x86 lib/xuggle-xuggler-noarch-5.4.jar com.xuggle.xuggler.demos.DecodeAndPlayAudio SND0(mega).AT3
theme song plays. (same with SND0(3rd).AT3)
Serio >
did castlevania work on xuggle 3.4? I'm thinking that might be mono.
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