I just upgraded from 3 to 4.
Do you know what this means?
It means that last time when HQPlayer was closed, volume setting was lower than what you have now as fixed value due to DirectSDM being enabled.
Due to recent change where you can adjust volume in smaller steps this tends to now run rounds. I have a fix for this coming.
However, DirectSDM defaults to off and I would recommend leaving it off so you get also DSD content upsampled.