Energy-dependent memory or NVRAM (Non Volatile Random Access Memory) is a type of memory device with random access that can store data in the absence of electrical power. For example, the settings of the first sound signal, which occur when the computer is booted, or the statistical data of the connected charger to the laptop or computer are also stored in this memory.
If we take the performance of some hardware systems in the device itself, then they also depend on the full performance of the memory, since it is in it that the necessary settings are stored, which are then loaded from it and activated, for example, sound or video.
For example, you can cite incorrect sound performance, you noticed that the sound on your gadget stopped playing out of nowhere. At the same time, you know for sure that there were no shocks, drops or moisture ingress into the Macbook or aimag. To solve this problem, first of all, you can solve the problem yourself, and for this you will have to reset the NVRAM memory, and after rebooting, pay attention to whether the sound has started to be played or not, if not, then, unfortunately, this problem is already related to the hardware part, and not to software and you will need to contact the service center.
As is typical for any physical memory, it needs to be serviced and periodically “reset”, for this it is necessary to perform the following actions:
after loading the Mac OS X system, turn off the gadget
after the macbook / mac mini / aimag will be turned off, it is necessary to simultaneously press four keys (ALT + COMMAND + P + R) and press the Power button, without pressing the pressed buttons until the apple appears on the screen and it reboots again, After that, you can press the buttons and wait for the operating system to fully load
If these actions brought the correct operation of your gadget, then the problem was directly in the memory. Good luck in using apple gadgets π