I've found a method of doing this using PulseEffects.
Install it
sudo apt install pulseeffects
Open it, select the speaker Icon in the top-left.
Click onto Applications, this is where you enable the PulseEffects modification for the sound made by specific applications.
On the left, open Filter and click the tick-box next to it. On some versions this might be called Low-Pass Filter.
Set the mode to 12dB/oct Lowpass, Frequency to 8000Hz, Resonance -3.0dB, Inertia 20.00ms.
A pass filter, allows frequencies through within the selected range. A low-pass allows low frequencies, a high-pass allows high frequencies.
I find this works decently, the audio is not distorted by a huge amount but the high pitch sequel is gone completely, I find it an improved situation at least. Adjust the Frequency to change the cut-off point of frequencies filtered out, which may help reduce distortion.
I've found a method of doing this using PulseEffects.
Install it
sudo apt install pulseeffectsOpen it, select the speaker Icon in the top-left.
Click onto Applications, this is where you enable the PulseEffects modification for the sound made by specific applications.
On the left, open Filter and click the tick-box next to it. On some versions this might be called Low-Pass Filter.
Set the mode to 12dB/oct Lowpass, Frequency to 8000Hz, Resonance -3.0dB, Inertia 20.00ms.
A pass filter, allows frequencies through within the selected range. A low-pass allows low frequencies, a high-pass allows high frequencies.
I find this works decently, the audio is not distorted by a huge amount but the high pitch sequel is gone completely, I find it an improved situation at least. Adjust the Frequency to change the cut-off point of frequencies filtered out, which may help reduce distortion.