sounds like could be hardware. also make sure the haptic feedback and /or vibrations settings are actived.
Sent from my GT-I9505 using XDA Premium HD app
Certified Couch Tester
Current: Xperia SP Stock
OnePlus One CyanogenMod 11S
Galaxy S4; Samy Deluxe Jelly Biafra
Nexus 4; Z1 ROM (xperia)
Galaxy S2; HellKat (Diablo kernel)