I own a pair of Sennheiser HD598 headphones and randomly while I am listening to music there is a little static that makes my listening experience less than ideal.  I was wondering if this is typical for headphones of about a year and a half of age, or if there's is anything i can do fix this...

I recently start producing some Electronic tracks and have noticed my cheap headphones don't cut it for the type of music i enjoy to make.  so i am looking for a set of over ear headphones with an overall good sound where i won't break the bank 0-350 USD price.