Skype is using 60% to 80% CPU

I have a Mid-2014 15″ MacBook Pro with an Nvidia graphics card.

Skype uses around 60% – 80% CPU on my computer when I make a call (doesn’t matter if it is video or voice call).

I tried doing SMC and PRAM resets with no avail. What could be the cause? And what would you suggest I do to fix it?