I had the same problem after repacking my wheel bearings about a year ago. You mentioned that yours had recently been replaced. Turns out that I did not tighten the left front one correctly and I had the exact problem that you describe. The noise didn't start until a couple months after I had repacked the bearings. You might want to check your front wheel bearings just to be sure and adjust if necessary. For me, it was a simple (but dumb) mistake that was easily fixed.
Matt
