Basic theory has its merits but don't take it as everything... if you only produce according to basic theory then no doubt your basslines, chords, riffs etc will sound old and just like every other tune - I spent a year of composing guitar music like this! to really get a 'different' sound you'd need to have a much more advanced theoretical knowledge, or just experiment!
I've got my grade 5 music theory and I'd say that definitely helps me when composing.
If you just want to learn the essential bits then just use google to find out about key signatures and basic harmonies (that'll help you with chords) and know that the main chords in any key are I, iv and V.
Yeah same here man, Grade 5 theory and Grade 8 Trumpet!
now, as the music has spread into so many sub genres theres some guys out there with classical training (guys like John B, London Elektricity etc) who have combined their knowledge of classical music with today's production techniques have taken things to the next level