Hello. WavesMaxx is bundled with the Realtek audio driver. Whether you have any WavesMaxx at all, or whichever version you get, depends on the audio driver that is installed. You can see all of the Realtek audio drivers that Dell has released on the Inspiron 3521 html page.

The ones for Windows 10 are WT. The ones for Windows 8.1 are WB.

If you know which version you had before, install that one. If not, go through them one by one until you get the features you are looking for. If you try to install an older driver, you have to completely remove the newer driver first.

1. Open the Device Manager (find it in the Control Panel, or type devmgmt.msc into the search box).
2. Expand the "Sound, Video & Game Controllers" section.
3. Right click on "Realtek High Definition Audio".
4. Click "uninstall."
5. Put a check mark in the option to delete the driver software, and then ok.
6. Restart the laptop. Because you removed the Realtek driver files, Windows will install its native audio driver, named "High Definition Audio Device".
7. Go back to the Device Manager and look for "High Definition Audio Device". If you see "Realtek High Definition Audio" again, that means that there was another version of the Realtek driver on your hard drive, and Windows found and installed it. So  keep uninstalling & restarting until Realtek no longer appears under Sound...Controllers and "High Definition Audio Device" appears in its place. At this point you can install an older Realtek driver.

If you try to install a driver meant for a different operating system, it might install okay, but generally you should use compatibility mode.

1. Download and save the audio driver to your desktop or any convenient location on the hard drive.  [If there are two "formats" on the driver's page, scroll down to the 2nd one, named "Hard Drive" format, and download that one, not the 1st one named "Windows Update Package".]
2. Double click on the new folder to extract (unzip) the driver files.
3. The extractor wizard will create a new folder for the driver files. It will be at "c:\dell\drivers\xxxxxx". Write down the exact location that the wizard creates.
4. If the driver begins to install automatically, halt (cancel) the installation.
5. Browse to the driver files on the hard drive (the location you wrote down).
6. Find the "setup.exe" file.
7. Right click on setup.exe to open the context menu.
8. Select the Properties.
9. Select the Compatibility tab.
10. Check the box "run this program in compatibility mode for".. whatever Windows the driver was meant for.

Thanks for your suggestion but it is not working after doing this I can able to fine dell audio in search but I can't able to execute that and it has gear icon instead of dell audio icon. I have added the image shows the problem. Please help me to delete driver's left over

I didn't try all 4 driver instead  I tried the one that works before resetting the PC.

And I can't find dell audio in control panel. I can only find in search just like in image that I posted

it is not working

What is "it"? Did you try all 4 Realtek audio drivers, and none of them had WavesMaxx?

I can able to fine dell audio in search

When you go to the Control Panel and click on Dell Audio, nothing happens?

Okay. If I think of anything else I will let you know.

Thanks I'm looking forward to here from you

Thanks for posting your solution! I will add that into my notes and it might help someone else.