That's what's happening to my HP Envy 15 as133cl laptop. Running Google Chrome poses no problems.

But when I run Mozilla Firefox, the laptop's Conexant audio driver has a program called Flow that does something related to figuring out what kind of audio your PC might want to play. And when Firefox is running, Flow can't seem to figure out what is going on and runs all the time, taking a large percentage of available CPU along with it.

I solved this problem with an Internet search. It was easy and painless.

After I installed the new driver, the problem returned. I'm lazy enough that all I did was bring up the Windows Task Manager (ctrl-alt-delete, then select it) and kill Flow from there. I haven't rebooted since, Flow hasn't returned, and I'm having zero issues with audio on the computer.

Update: It's annoying that killing those two processes doesn't stop Flow from killing laptop performance. There is a third Conexant process that I should kill to see if it takes care of the Flow problem. Why it's STILL a problem, I don't know. If it affected Chrome, it would cause a major uproar and be fixed in a week or less.

Eventually I needed a Chrome-equivalent browser, and I turned to the Fedora-packaged Chromium. It runs great, and I like that it's packaged by Fedora developers.

But it ships without the codecs required to watch video from places like YouTube.

It didn't bother me for awhile, but situations do come up where I need to see a video, and it's a little interruptive to start Firefox if I'm not using that browser already.

So I did a little web search and learned that there is a package from RPM Fusion that will take care of this issue.

If you already have the RPM Fusion repositories set up on your Fedora computer (and I recommend that you do it if you haven't already), just open a terminal and run this:

$ sudo dnf install h264enc

That will get you video in the Fedora-packaged Chromium browser. That's it. Easy, right?