Yamaha DTXpress/DTXplorer/DTXtreme

Hey guys,ive had my dtx2 for about 2 weeks now and although this may 
sound like a really stupid and easy to fix problem,its had me 
stumped for the last 24 hours.Im getting no sound whatsoever from 
the pads when i hit them,although im getting sound when i play back 
stuff i have recorded previously.this is the case with ALL the kits 
and i am at my wits end as to what the problem may be.The last thing 
i was doing when the problem occured was looking for a sound to 
assign to the rim of the snare,and it was one that kept looping so i 
was trying to stop it when i lost all sound from the pads.it wasnt 
like i was mashing buttons,all i did was flick between voice/song/kit
(i now know how to stop that properly now,having read 
troubleshooting in the manaul!), while hitting pads before it 
stopped.But now of course,i have no sound at all from the pads when 
i hit them! i have checked all cables,and the fact that i get sound 
when i play back recorded tracks/songs makes me think its a setting 
i have changed by accident.Any help would be greatly appreciated,i 
have been through the troubleshooting in the manual but have had no 
luck with that at all.Thanks in advance to anyone who may be able to 
help me with this problem,life is somewhat dull without my e-drums:(