I have replace my 64inch lamp bulb once before ,maybe 6mths later the the picture started to fade but the sound is great,I hav

[Mamalo]

I have replaced my Mitsubish serial # 245070 model#,WD 60735.....Manufactured in 2009..64inch lamp bulb housing,6mths later the screen started going black again,but the sound is great.i have since order 2 more from Amazon neither one of them fix the problem

 

[americanaudiophile]

Since changing the lamp is not helping it seems that the power supply and or the ballast circuit which drives the lamp have problems.
It is less likely but generic low price lamps will not perform the way the original did. Should still be bright at least when first installed. If the original lamp was made by say Osram is is a good idea to get that same brand and model rather than a generic.