If you boot into Safe Mode, does the issue continue?
I would recommend running either MalwareBytes Anti-Malware
or Super Anti-Spyware
or even both to see if something is detected.
It's also time you take a look at everything running and starting up when your computer does.
I would recommend using Autoruns
Not sure what all those things are? Go to HERE
for help with identifying those pesky startup items.
The issue is still persistent in Safe Mode, and i did a full system scan with Avast and it said there was nothing