LTX 1040 drive belt

Replaced drive belt with a $11 kevlar belt 92 1/2 inch from E Bay. Belt seems to slip when going up small grade and turning and makes a whining noise. Do you think it is belt noise due to buying a cheapee or maybe coming from a pulley. Mower is a 2012 Cub Cadet LTX 1040 42 inch 5 years old. Thanks T

A whining noise? I can understand it slipping (cheap belt) but I've never heard one whine before. the oem part number is 954-04208 . Or 754-04208. .
Did you get it on the very bottom section of the transmission pulley?