im had the same prob. first time u get in mud it comes off.
Mine turned blue also and so did the dried mud that fell from them in the back of the truck.They did it a couple more times now they are ok.Cleans up with soap and water.i just got some new itp mudlites about 2 weeks ago and had them on the road for the first time yesterday.....and they turned blue i wondered if anyone else has had this happen to themand why they did this?