My 99 A4 Avant has had a strange noise coming from the front end for a while now and is getting worse only recently. This all started when I replaced the tires the first time. I had Americas/Discount Tire replace the stock tire and it seemed like they never got the balance right for the wheels. After 7 visits and rebalancing, the noise was less noticable, but still there. This was still true until recently. I had the 90k service done, they recommended new tires and alignment. Had this done and noise still exists. It is a wub..wub..wub sound the increases in frequency with vehicle speed and is more noticable when you are turning. My thoughts are either the wheel bearings or a CV joint is going bad. How hard is it to replace these? Anyone have any thoughts?