I have entered the 3 digit code for my TV (Sony KDL32EX403) on the Humax remote control (RM-109U), but afterwards pressing the TV button and standby on the Humax remote has no effect on the TV. Likewise I am unable to take the TV off standby by using the Humax remote. I entered a valid 3-digit code as it got the TV to power off - is it possible that another 3-digit code is also valid and it will work in controlling the TV from the Humax remote?