Realtek Audio: Bass Increases as Volume Decreases

Question

I have two ways to change the volume of an application on my Windows laptop:

• Change system volume (Native OS controls)
• Change application volume (YouTube video)

When I change my system volume, the bass stays the same. However, when I lower an application's volume, the bass becomes louder.

Here are two audio files of the same song demonstrating the difference:

• Application volume 100%
• Application's volume set to 3%, but amplified to 100% to hear the difference

Difference shown visually with spectrograms from Audacity: Top: lowered application volume with bass-y sound. Bottom: normal volume

About four months ago, this was not a problem. The equalization of any sound played would stay the same no matter the volume. Mid-video, an automatic Windows driver update occurred and the difference was quite pronounced.

Does anybody know how I can fix this issue? Is this intentional? I do quite a bit of sound sensitive work and it makes listening to older projects difficult because the mastering sounds all wrong. Any help would be appreciated.