Sent to Apple ... (as Developer Feedback) and to APPLE (CEO)  Get this problem FIXed Now to avoid a BIG Class action ... It is corrupting Mac Speakers ... And will cost Apple a lot! Shortly after installing Catalina or Big Sur to MacBook Pro (and on many other Macs) … the speaker output becomes corrupted. The same issue, described by numerous others in the above link, occurred with the Left speaker on my Mac.    It occurred just after installing Catalina and Big Sur to a 2015 Vintage MacBook Pro development platform with a million bucks of important softwares.  The sound control panel has been modified by Apple in these latest macOS releases.  There is obvious serious trouble with it. The speaker balance slider in the sound control panel was defaulted all of the way over to the Left when I first looked at it, (which was odd after installingl these macOS’.)  I expected the balance to be centered by default. It kept jumping back to full left whenever I attempted to adjust it to the middle. I strongly suspect a macOS cause of a hardware flaw or outright breakage.  (Hopefully not an intentional malicious and nefarious act on Apple's part to get folks to go out an upgrade their machines.)  A prior Apple macOS software update wrecked my MacOS keyboard at one point in the past. Apple did a recall that machine and I got them to fix it after lots of consternation and denial and resistance from Apple.  (A speaker repair costs around $600.)  I have been a Apple developer for 30 years. 

Plenty of attorneys will be very pleased to take on a case like this one (pro bono). Someone must force Apple to recall and repair, or replace, our gear since they are the ones that cause the problems to our machines through their shoddy software releases, half-baked workmanship, derelict change management, and poor internal quality control measures. Apple uses us as testers to help discover their own flaws, as they destroy our machines with their corrupt business practices, while trying to make more money off us 20 million + developers. It is just wrong and needs to be pointed-out publicly in order to get their attention and get fast action to resolve these problems! Otherwise, they just deny a problem's existence and never admit it's their fault. Apple delays doing anything about issues, as long as possible, until it burgeons and festers and propagates like COVID.

Mine crackles with or without the simulator running. The only time it does not crackle is listening to sound through headphones via Bluetooth connection.

Mar 18, 2021 at 7:29 PM ORIGINATOR Update to this problem: Besides the speaker corruptions mentioned above after installing Big Sur, It has actually expanded and Warped the top and bottom of the case, likely from overheating the internal battery, which may have lead to the speaker issue as well. The Mac no longer sits flat on a desk top but now rocks on the bottom of the case and the top screen of the machine no longer completely closes either due to the deformation of the case after installing Big Sur! I am very upset about all this. Today I called Apple to have them send me a box to send in the machine to repair it for me. I have already had to prepay $640 for that job and estimate to fix machine C02R90KQG8WQ. The fan is running loudly and the edges of the screen are separating from the heat. I believe that all of this relates to installing Big Sur onto the Mac.

From Apple to me re: Feedback reply Mar 18, 2021 at 4:57 PM – FB9047661: Xcode Simulator Accessibility Spoken Content Problems Xcode & crackling speaker output while simulators are open on Macs running Big Sur: Apple: After reviewing your feedback, we have some additional information for you, or some additional information, or action is necessary for this issue: Please verify this issue with Xcode 13 Beta 5 and update your bug report with your results by logging into https://feedbackassistant.apple.com/ or by using the Feedback Assistant app. Xcode 13 Beta 5 (13A5212g) https://developer.apple.com/download/ Posted Date: Aug 10th, 2021 For a complete list of logging instructions visit: https://developer.apple.com/bug-reporting/profiles-and-logs/ My reply to Apple: Sorry, I do NOT run Beta Softwares on my machines anymore. I will let you know how the final Gold Master release works.

This Navigation Bar Transparency problem began when Apple made Dark Mode. I told them about it and Apple fixed it but they have broken the Nav Bar again in iOS 15.