if I'm not mistaken, what you're using for the "wub wub" here is just an instrument with a weird long attack... from what I've heard of the wubby wub type of dubstep, this instrument you've got doesn't remind me of the wubwubs
I've left a timed comment on your soundcloud making a more specific point about your bass instrument ;D
in current popular dubstep the wubs are normally made with LFOs on the volume, compression, distortion, and assorted filters. for example, if you have a bass sound (with distortion and a lowpass filter) and you automate the instrument's volume knob and the filter's frequency knob in unison, that's your wub
automating knobbies is fairly basic, so the internet or even the help file for your DAW should definitely have something about it