2004 Acura TSX never should have purchased in the first place

I should have done a better job looking at this car before I purchased it, but I can’t change that now!

My car will at random times lose power to the radio and GPS. It will happen at varying speeds (low speeds, when I am on the highway, when I am shifting gears, when the car is just stopped at a stop light). The music stop and the GPS turns off. It’s almost like the car is idling low and almost stutters, then the music will come back on and the gps will come back on to the intro screen. I replaced the battery in the car about 6 months ago and it seemed to fix it for the first couple weeks. Then, the car gradually started doing it again. I had the alternator tested at Advance Auto Parts and they said the alternator and battery were both fine. Please help! Any ideas!?