STRS6707 problem

im fixing a tv. Sony KV-G21MJ2. i've changed the regulator IC STRS6707 and it works. The next day i turned it on, the regulator ic get shorted, making the fuse to get open. tried to replace it again and it works. but the same thing is happening. today will work and tomorrow the ic will get shorted. i wonder why, could this be an issue of genuine parts? i've already change it 3 times now and still the same thing. need help pls.