What type of audio-file do you try to load?
Atm MP3 is not Supported
Supported are:
* wave
* ogg
* ds
* flac
Besides that, since you are new in Forum
Welcome maksou !
Here are all important links:
http://lmms.io/forum/viewtopic.php?f=1&t=4740
-A few rules and useful forum instructions
If you like to introduce yourself, to the community, go here:
http://lmms.io/forum/viewtopic.php?f=4&t=4480