Clicking sound under driver's side

I hear a flapping/clicking sound that gets faster/slower with the speed of our 4x4 Nissan Frontier on the front driver’s side. It sounds like a baseball card against the spokes a bicycle’s spokes. It started one day a couple months ago, and hasn’t gotten better or worse since. Any ideas?

When you say “under driver’s seat” do you mean the sound comes from inside the vehicle or from underneath?

The sound comes from underneath the vehicle. Hope that helps.

Yes, that helps. I suggest you look for something contacting the wheels or the driveshaft.

What year is your Nissan, and how many mile has it accumulated?

It’s an '06 with about 60K. My husband and I have guessed that it was something with the axle or driveshaft. We had the transmission and clutch replaced a couple of months ago, though the sound did not start until a couple of weeks later. I am thinking about bringing it into the shop this week. Any tips on questions to ask or observations to make would be appreciated. Thanks!