my DC may be @#$í up.

Well it's not a major problem yet but I'm just wondering.... I was playing my recently burned Sega GT last night (there wasnt any problems until then) but when I played it today, one of the race tracks won't load! (it loaded fine yesterday, and all other tracks loaded fine). I tried my other games to see if my DC was broken but they all worked without any problems. I dont think there's anything wrong with the Sega GT CD, and my DC is only 2 months old so it can't be because the laser is worn out or something like that. What should I do? Should I clean the lense? If so, how do I clean it? It doesnt even tell you how in the dreamcast manual.