Same here. My friend. Toggling the button doesnt seen to make any difference. Also sounds are extremely loud (cars , explosions , plane in PUBG).  Tried to install an older version of synapse but it didnt work beacause it keeps updating it self. In general the overall volume is louder tham before. If i uninstall synapse volume returns to normal. Hope they release an update soon. 

Same here, if there could also have a way to see how the sound normalization is being applied it would be nice. I don’t even know what 10 or 50 looks like. I use a small app called “Sound Lock” that allows me to see where the limit for high volume sounds is limited at and how high some sounds are being blasted in my ears and it allows me to see where I’d want to put that limit. Like, where I would think its comfortable for my ears.

This same thing happened to me this morning, it installed the update and now if i toggle my mute button on discord i wont hear it unless i tab it 4-5 times… thank god for “automatic updates” it’s really amazing.
It also doesn’t seem to change anything if i set it at 10 or at 100, it makes 0 difference.

Also for some reason everything was so much louder after the update so my ears almost got blown out

Think i fixed it. I uninstalled synapse und just installed Firmware v0011 r1. 
you can find it here https://mysupport.razer.com/app/answers/detail/a_id/3531/~/razer-blackshark-v2-%7C-rz04-03230-support-%26-faqs under Drivers and Download.
But you cant use Synapse, hope they fix it soon.

It works for me.
Sorry for bad english ^^

This worked for me with the latest firmware update. Still cannot use Synapse though. Is this issue really not fixed yet after this long time??