In the past month or so my '11 SuperCab has developed a rattle on the driver side. It sounds a little bit like plastic hitting against plastic and makes itself heard everytime I hit a bump (i.e. almost constantly). At first I thought tt may be coming from the gauge cluster (I’ve removed the trim from around the cluster but to no avail), or that it may be coming from around the knee bolster area. I've pushed, pulled, and grabbed all around and can't seem to find the source. Anybody else have this issue and/or know where the source might be? Thanks.