2009, Annoying High Pitched Whine when Playing Music via Bluetooth Adapter

Yeah the '06 Corolla is a bit of a different animal a clean or burning engine and all this sort of thing but be that as it may. What is on the Prius right now? You may get it a little lower You may not get it to stop once it starts in the one NZ it's pretty much going to be a thing these engines are dirt cheap they can be rounded up everywhere and all parts of the world without issue if that becomes a thing I don't know I have an '09 that burns oil If I drive it my normal hundred miles a day or so once a week it'll be halfway down the stick with this car I generally let it get down almost to the bottom dot and then top it off to the upper dot never overfill I use cheap oil that doesn't really cost me anything so there's always that I have three other generation twos that don't burn oil at all the '09 is a work vehicle. The '09 also has 350,000 on it and it will probably never get its engine changed and I should be able to get it to 666k possibly beyond but it'll still be using oil like it is now or possibly more.

 

If you can, try temporarily powering the adapter with a battery.

If the noise goes away, then your problem is a ground loop. If it remains, you'll have to keep investigating.