My husband has been commuting from Hermitage to downtown Nashville on the Greenway and every day he comes home with metal shards in his tires and has to fix a flat. Has anyone else been having this problem? Anyone know where on the road/trail these shards are coming from? They seem to be someplace between downtown and Shelby Bottoms, but we can't narrow it down exactly because they result in such a slow leak. Thanks for any help!