Drop in sound quality/loudness

[alandbush]

Did you try playing with a different source? Could be your original source has an issue with output gain?

Another thing I noticed was that the music originally sounded quite high in the beginning but quickly (but not that noticable) faded down to a lower sound pressure level.
Hard to explain what it sounded like. This could of course be due to the SAM or DSP feeling to much pressure in the low frequencies, but like I said, this has not happened before to my knowledge.

That describes night mode perfectly. I would check that setting again.