Sound control when second monitor is connected

[tutusik]

Hi,
I have macbook pro 2018 connected with LG 27uk850 with USB-C. In the monitor I have put speakers logitech by cable.
Question is: How can I control volume of speakers in macbook?
Is it possible? I tried to search on Google but no answers

I found this Sound Control. It seems to be good but it costs 11$: https://staticz.com/soundcontrol/?f...OkvJody9u_om0NSXmIHT9BevpHGHAqEhg4fhZk9Mm4uF8