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How to EQ the System Audio on a Mac Using eqMac
The Apple Music App has an EQ with plenty of presets for the average user. But what if you want to adjust the sound in Safari or Spotify on the Mac? Here's how!
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There are plenty of other applications out there such as Boom, Audio Hijack, and Airfoil, but if you are looking for an easy to use and free equalizer without a lot of bells and whistles, the open-source eqMac just might fit the bill for you
eqMac - Free Audio Equalizer for macOS
Answer: Sometimes there are synching issues, try to switch away from eqMac audio device to your preferred output device and eqMac should restart the audio pipeline. Alternatively, you can try to restart eqMac, that should help as well
eqmac.app