ok, thanx for idea how to test audio interface. so I used it as default sound device in windows for playing and recording music.
when I play music through u46 it's ok, when I play vinyl from turntable(turntable->u46->mixer->speaker) the sound is clear(good) but when i recorded a tune the sound was horrible. I did a little record in wav file, here is link to it(no viruses:)
http://uploading.com/files/c69a6mc3/test.wav/sound drops all the time in that record. so what can it be?