Apple Catalina Appears to Introduce Massive Jitter - SOLVED!

Mark Tinka mark.tinka at
Thu Nov 12 15:57:11 UTC 2020

Thanks, J.

So I did test this a few times as well. The only thing I had enabled 
(during the first test) in "System Services" was "Find My Mac". 
Everything else was turned off, and the issue remained.

Just to confirm that this was a clean install of Catalina, so the only 
wi-fi AP in my history is my home one, as I haven't worked in a cafe, 
airport, or hotel since then :-).

Since disabling Bluetooth and the system stabilizing, I've re-enabled 
"Location-Based Suggestions" and "Significant Locations" only. 
Everything else under "System Services" is still turned off, including 
"Wi-Fi Networking".

That said, you did mention that you've fixed this on Big Sur. I am still 
running Catalina. Considering Apple's history of dodgy initial releases 
of a new OS, I'll give Big Sur a few months (or a year) before I feel 
it's safe to upgrade. I'm already having to deal with Catalina as it is, 
which is why I have High Sierra installed on my old laptop for my 
weekend DJ streaming habit :-). OBS Studio seems to like High Sierra 
better than Catalina, hehe.

Many thanks for working on this - it's most appreciated!


On 11/10/20 16:30, J. Hellenthal wrote:
> Hey Mark,
> Went through a bunch of tests here. Seems I’ve cleared up the matter on this macOS[1] Big Sur at least by disabling Wi-Fi Networking under “Location Services -> System Services -> Wi-Fi Networking [2]”. It seems at least from perspective that something changed there and causes the Mac to scan more aggressively when more than one access point (generally speaking your SSID & SSID + 5G) has been logged at a location as accessible. This same thing could be observed at least on my system while having those settings turned off, bluetooth on and location services enabled and opening (Wi-Fi Explorer[3]) which puts the interface into “monitor mode” which seems to be causing the contention somewhere. After those changes keep in mind I had to restart from a full shutdown to get to some real clean ms traffic to the router and I prefer to be connected to 5Ghz before 2.4Ghz.
> 1. Darwin Kernel Version 20.1.0: Thu Oct 29 05:35:40 PDT 2020; root:xnu-7195.50.5~4/RELEASE_X86_64
> 2.
> 3.
>> On Nov 5, 2020, at 00:43, Mark Tinka <mark.tinka at> wrote:
>> Just an update on this re: the Bluetooth.
>> I had my AirPods paired previously for single use. I don't use them on the laptop (there is some latency), so I prefer the wired earphones. But it seems like Bluetooth was aggressively scanning for them. After removing them from the system, the scanning remained, but reduced significantly.
>> So looking at Console again, every so often, Bluetooth is scanning the network on behalf of the "sharingd" process.
>> sharingd is a sharing daemon that supports features such as AirDrop, Handoff, Instant Hotspot, Shared Computers and Remote Disc in Finder.
>> Still keeping Bluetooth off, however.
>> Mark.

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