First, run the Playing audio troubleshoot - open Start > Settings > Update & security > Troubleshoot
Scroll down, select Playing audio
Click Run the troubleshooter

When complete, restart your computer then check if audio is working again.

Press Windows key + X
Click Device Manager
Expand Sound, video and game controllers

Right click your audio adapter
Click Properties
Click the Driver tab

Is there an option rollback?
If so, click it.

Open Start, type: change sound card
Select the Playback
Right click your Speakers
Click Set as Default Device if it isn't already

Select your speakers
Click Properties
Click the Levels tab
Use the slider to adjust level

Man, I never told my speakers are working, I told that the MaxxAudio Pro app doesn't work while MS Teams is running. Without that application the sound is very low both in sound level and quality.

I have tried every method given above before asking this question in dell community! Please suggest me different thing which doesn't deal with uninstalling drivers and rollback. I have tried it a hundred times!!!!

Please help!

These seems complicated 

If the problem is team there is hardly any one can recommend here 

Launch Teams with WaveMaxx EQ off and than turn them on while in Teams

What if your Default Audio Device in TEAMS ? 

For Me it's System default and I am using a USB headset 

WaveMaxx works fine