This refers to my setup, results my vary with different setups. My setup Snakeoil Squeezelite player > USB out > DAC > Amp.
Overall if vol adjustments are not too fast and done one at a time, this worked fairly well.
If the LockVolume LMS plugin setting was set to 'Lock player at current vol' (the most useful option) then there was audio interference on vol changes. Other settings of LockVolume had no interference. All settings on a SB Duet player had no interference on any setting.
It appears that the script does not detect all volume events. In the WebGUI, there is a volume slider with vol + and - buttons on the ends. All adjustments via the slider are detected but nothing for the buttons.