Immediately press and hold Option, Command, P and R keys for about 20 seconds and release them when you hear a startup sound. To do this, shut down your Mac and power it on again. A sound card (also known as an audio card) is an internal expansion card that provides input and output of audio signals to and from a computer under control of computer programs. This happens because the computer restores your hardware’s default settings, and sets the internal hard drive as the startup disk. Reset it to clear any glitches with any of these and other attributes. Your Mac laptop uses nonvolatile random-access memory to store different settings such as sound volume, time zone, display resolution and recent kernel panic information among others, and access them quickly. If you find audio not working on your Mac laptop, try updating your operating system to the latest version and see if it fixes the audio issue. Apple also improves and fixes audio latency, reliability of USB audio issues and other related user concerns. GODSHARK PCIe Sound Card, 5.1 Internal Sound Card for PC Windows 8 7 with Low Profile Bracket, 3D Stereo PCI-e Audio Card, CMI8738 Chip 32/64 Bit Sound Card PCI Express Adapter. With EAX 4.0 drivers now available, make sure you use the most recent sound device drivers from your sound card manufacturer, as well as the latest version of.

Each time a new macOS is released, it not only comes with improvements and new features, but also changes in audio drivers, kernel frameworks, Unix tools, new bugs and sometimes audio issues follow.

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