Ok, take a listen to the sound clip, it's just some dry supersaw hits made with Superwave Trance-Pro. You hear the difference of the first 2 hits and the rest?? it's weird, some sort of phase-issue, and sounds, well, BAD!

I have this issue with other synths and sequencers as well (was using FLoops Studio at the time) and for 1 or 2 seconds after I press the play button, this happens.. (It happens when the first sound comes after I press play). It seems to be bound to multi-oscillator sounds, and it's somekind of a phase-something-something issue... Like the waves a cancelling each other out or something. But why does it only occur in the beginning? and how do I get rid of it? Anybody know??

http://www.network.is/valdemar/Phase.mp3

btw. I usually solve this by adding a couple of notes at the start of the song, before the actual song begins. If I do that, the issue occurs before the song begins and doesn't come again, because, like I said, this only happens on the first second or so, of sound played by the synth. Then I just cut that part of the song afterwards.
but still.. it's friggin' annoying!

Yeah, its a known problem with the trance pro, quite annoying at first but you get used to it. When it comes to rendering your song, just put the pattern or riff that uses a trance pro at the start and edit it out in a wave editor.