Just a thought. Are you sure your unit has soldered in RAM (if indeed it's a Mac mini 2014 that is)? According to the following link from 6 years ago the RAM is not soldered in. https://www.youtube.com/watch?v=wF5mz---Ylk
Just a couple of thoughts. Try using USB keyboard to try and eliminate the regular keyboard as a problem source. See the following link on how to boot into Safe Mode from a terminal if you manage to access "command S" again. http://osxdaily.com/2014/09/04/enable-safe-mode-boot-command-line-mac/
It seems from your description that you hear this static noise even when the volume is turned completely off which to me could imply that you are getting some kind of electrical discharge, like for example, jumping across from a component to ground shielding or a piece of metal. If have the unit opened up in a dark room, that effect should be readily apparent and the source identified. If only hearing it when there is some level of sound volume applied that would probably point to electrical noise/interference being injected into the audio circuitry. In either case though, as a first step in isolating the problem, after powering up the unit and once the noise is apparent, use a non-conductive tool, such as a plastic spudger, to move wires or components and prod cold/cracked solder joints to see if the sound is eliminated or gets worse. If the offending component is found and the situation rectified (ie securing loose wires or connectors etc), then all well and good; if not you will have to used additional...
I know next to nothing about these units but the following seems to suggest there might be a couple more areas you may want to research before attempting any hardware repairs: Still getting EFI error tones after replacing PRAM battery This may or may not be of use. Mac mini Mid 2010 Repair If considering doing hardware repairs to the unit, you might as well just go ahead and open it to check voltages, fuse presence, a visual inspection for damaged components/traces, cold/cracked solder joints or loose connectors. At least you are one step of most of the participants asking here.....you actually own a multimeter! lol :-)
Sounds like you have inadvertently installed new software or a browser add-on that includes redirecting routines. Either uninstall any new software you have recently installed or if applicable start your Web Browser in Safe Mode to disable any add-ons or you can (again if applicable) disable them or you can completely uninstall them. You may have to reboot your computer too after uninstalling etc.
Could be the automatic defroster element/circuit has stopped working and ice build up has stopped the fan that sends cool air into your upper section. When you unplugged it, the ice melted, and once plugged back in, the fridge worked again due to the fan being back in operation, until the ice built up enough to once again stop the fan from rotating. This condition will keep occurring until the problem with the defrosting circuitry has been repaired. Edit: Probably a good idea to post the model number so that the more experienced participants here have an easier time with helping you resolve your problem. :-)
copied and pasted your exact question along with -ifixit and macbook and the following is the first hit returned: https://apple.stackexchange.com/question...-white-thingy-below-keyboard-button-is-broken Apparently they are known as scissor clips or B-clips but I shall forever fondly call them "that white thingy under the key"! :-)
The following command will completely shut down your computer in Windows: Right click Start icon and select Command Prompt Type or copy/paste the following in that window: C:\Windows\System32\shutdown.exe /s /t 0 After your computer has shut off, restart it again and then try testing shutting down as normal. If computer still won't shut down, please post what operating system the computer uses and your method for shutting the computer down.
Your screen is experiencing what is known as a "moire pattern". The following may be of use to you and I am sure the Apple experts participating here can give you more advice if required: Is the LCD broken
Right click on the speaker icon in the taskbar notification area. Select sound. Select playback tab, double click on speakers, select level tab in speaker properties click on balance. Now adjust the sliders so that one side cuts out while sound is still coming from the other side. Repeat for the other speaker. You also try using VLC -> Audio -> Visualizations to see if VLC is processing the audio signal from both audio channels as it may not be your speaker itself that is of fault but a component in the audio processing circuitry instead. As for replacing a speaker, googling or youtubing for “teardowns” or “repairs” plus your model number usually produces positive results.