TapNoiseIf audio seems much louder on one side, check System Settings › Sound › Output and the balance control for the selected device. A centred balance is a useful starting point for diagnosis, unless you intentionally use a different setting.
Test the right output
Choose the device you are actually listening through. Settings for a display, headset and built-in speakers may differ, and some devices expose fewer software controls.
Play a known audio source, then compare another app. If only one application seems uneven, inspect its own pan or routing settings before changing system-wide balance.
Understand spatial typing feedback
TapNoise gives keys left-to-right placement across the stereo field. A left-side key and a right-side key can therefore sound spatially different even when the Mac’s balance is centred.
Test a short phrase with keys from both sides rather than repeatedly pressing one key. A theme’s stereo design is not proof that a speaker or earbud has failed.
Check physical causes carefully
If the imbalance persists across apps, inspect the connection and try another device if available. Do not raise volume sharply to compensate for a missing side.
If you prefer all audio content in both channels, mono audio is a separate accessibility option. Keep an intentional personal balance setting when it suits you; the goal is to explain unexpected behaviour rather than force every setup to the same values.
Source: Apple’s output balance controls.