iPhone 4S high pitch noise
I've noticed a suddle but noticable high pitch noice whenever the iPhone is connected to a stereo via the headphones jack. This is especially noticable in my car. The noise starts when any audio output comes on (Siri, unlocking phone, Music app, Spotify app) and goes away shortly after audio is terminated. My old iPhone 3GS does not have this problem even with the new iOS 5 update.
Has anyone noticed this? I can't listen to music on my iPhone in the car because it's annoying.
Thanks,
Dawid