Good but a few things you could improve
I kinda liked it, but you tend to make your intro's quite long. That first sound you heard really goes on for a real long time and gets very annoying. Also that sound you used was the only thing making it sound a tad sad. I really have to agree with the response of Flared24. Honestly that sound is just annoying. When i dont feel so good i tend to put on some sad music you know. But this is not really something you would put in a list of sad music. Also the bass you used was way too high. My speakers are quite good, but they just couldn't handle it, so they wont play any bass at all. (and yes, i know you told the people that, but if you knew it already, why didnt you change it?) Also this piece was more of a trance then drum and bass. I usually say the opposite, but you used the same melody the whole time with the 'sad' sound playing too, so it sounded more like a trance then a drum and bass song.
Just one more note, at the absolutd of the song, the sound suddendly stops and then the song starts again as always. If you would have cut out the part where the music stops, it would have been a loop as well.