Cant hear anything but "Purring" on Gmod Hldj

[saimaannorppa]

So I start the hldj, and the gmod tab, the hldj start normally.
i choose file to play and when i start playing it i hear Purring kind of sound.
:O
The music files are 11025 hz so i think it should work on gmod, please help :/
this works on css