The layering of compression really does get you. I've noticed (both in "Plexamp in my car" and "playing music on Twitch" contexts) that using a FLAC source makes an audible difference, even compared to a high-bitrate MP3 source.

This might seem pretty obvious, but I wasn't expecting it to matter as much since the end result was compressed again (and yet again on my car's Bluetooth) using a different codec.

This isn't on anything close to audiophile gear either. My car stereo is thoroughly mediocre and my home stereo is speakers I literally found in the trash.

Now I'm (belatedly) rebuilding my music collection in FLAC...