Do you host your server tf.lua.kr out of our home or something? If so, the connection path for yourself and everyone else is different.
Are you sure that you and only you can use Jukebox and 100% no one else can, or is it just a few people here and there?
Jukebox doesn't use Java VM which requires a download, it uses Javascript which is built into browsers. Users do need to have Flash for Other Browsers installed. This is the same version of Flash that Steam itself requires.
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