Brake noise

[TVB]

Lately I've been hearing an intermittent noise from my front brake. It sounds like the disc is rubbing somewhere once per rotation, but it doesn't happen all the time (I keep thinking it fixed itself, then it comes back) and it stops when I'm applying a little pressure to the brake lever. Visual inspection gives me no clues, but I don't really know what I'm looking for. Any ideas what it might be? More to the point, I'm wondering if it's something that's likely to be a warranty issue... because that affects whether I bring it to a convenient non-authorized dealer, or an inconvenient authorized one.

[hardd1]

buy a can of brake cleaner ... spray the caliper and rotor...some disc brakes make noise from time-to-time....a shot of spray cleaner helpss