Yamaha DTXpress/DTXplorer/DTXtreme

Friends, 
 
    Suddenly am facing this weird problem in the dtxpress. I usually
record my practice in the dtxpress using the "rec" function .....
typically i would record, listen to it, get the faults and delete the
track  (sound edit -> clear track option) ....... 

but now suddenly it isn't recording properly i can only hear the
various   pad hit sounds on the measure that i select. (means if i
select 4/4 measure with quarter notes, then it would record only the
notes/hits on 1,2,3 and 4th counts.... the other hits are missing) ... 

Please help whether i messed with my dtx setting somewhere ?? Will
reset'ing to factory setup help ??? 

Please share your inputs, 

Best Regards.