Light Timer Malfunctioning

i have a tiny grow going right now and i'm just using a cheap timer from target. long story short, i think the timer is a little slow because the lights are on a different schedule each day even though the tabs never change. does anyone know of a reliable timer under 20$. maybe from a home depot or lowes? i need a new one, but i don't want to go out and get another piece of garbage...or does anyone know how to fix this thing?

this is the one i use works great sorry dont know the brand name got it at home depot for little under 20$

alright thanks a lot man, i'll go check it out today.

i got mine at osh for about $5-6, push button tabs it aint let me down yet, im actually really satisfied with this one. i tossed the package but its a little white square one. check it out when you can