Is this normal?? Ticking buzzing Victron battery charger

SamG340

I picked up a second hand Victron 24/50 skylla-tg charger , got it set up on my batteries, seems to be working well but it's making some humming and buzzing and ticking noises ... Is this normal ??

Video click to view

https://youtu.be/XDl0j6CDb-A

You might have to turn your speakers up to hear it , it's not very loud

Is it meant to be making all these little noises ?