Hi , i got a Optoma 72i , had it about 14 months iv'e got 712 hours on the bulb . The last 2 days its started turning its self off after about 30 seconds . Is this normal 4 a projector having only 700 hours of use ? . I thought if the bulb was due to go it would just get dimmer untill it was spent . The bulb is still really bright and picture fine  .Any advice would be great as i'm not sure whether to replace the bulb or maybe there is another reson why this is happening . Thanks in advance .