i just noticed a noise today on my 2013 3.6R outback. it sounded exactly like a pebble hitting the windshield on the fwy, but it came from outside below the driver side door. at first i thought it was a pebble hitting my windshield and ignored it. then it happened three more times and noticed that the noise really come from outside of the driver side. the noise is fairly loud. it happened intermitenly. i heard it four times in a 40-minute drive. i have no idea what its. this is the first i heard any odd noise from my OB. i've had it for about a month and it has about 1k miles. has anyone heard a similar noise from their OB? thx