This exact thing happened to me, clutch was changed right before I bought the car. (wife works at a dealership so I saw it in process) Although I suspect it was the quality of the "OEM" kit they used. Having owned only 1 automatic in the 25 years I've been driving, I knew it was the TOB. If it you hear the grind in neutral with the clutch pushed in and revving to ~4k rpms, it's your TOB. I had them change it out to an Exedy stage 1 and have never been happier. Feels much more like the WRX I test drove.