How to dampen high pitch frequencies in bad speech audio recordings?

Many livestreams or recordings with spoken content are made through video conferencing software which compresses audio in such a way that high frequencies of the speech between 3500 and 10k Hz are painful to hear, which you encounter mostly when you play back video clips or podcasts derived from such software. Can you recommend a solution to normalize this bandwidth when any audio is streamed into any output channel? (any headphones or inbuilt audio speakers) **Wavelet** seems to be a privacy-oriented third-party tool with good user documentation. But it seems a bit tricky to set it up on a multi-user system such as Graphene OS if you prefer not to use the command line on the mobile device. I also found two other candidates : **RootlessJamesDSP** and **ARISE Sound Systems** Is there any sort of Equalizer that is built into the Operating System, how to find it? Or should it be a third-party app, and which one?