At my greatest aspiration, I'm no more than a casual music listener - however I am very conscious of pitch. On more than one occasion, I've noticed that a song I'm familiar with seems off pitch, as in lower or higher key than I think of it in my head - and I seem to notice that particularly around shitty speakers or bluetooth or some combination of the two. Glad to know I'm not crazy :)

To your point, I would lean towards bluetooth as I've never associated the phenomena with Pandora. My friends and I mostly use Spotify.