Mac OS handles it and appears to scale the menus to usable levels. I’m not aware of an option to adjust this (other than through Accessibility panel) and it didn’t change between 2.3.0 and 2.3.2.
Hi
I’m having exactly the same issue with the following:
iMac Retina 5K 27 inch 2019
3,6 GHz Intel i9 8 cores
RAM: 32 Go 2667 MHz DDR4
Video: Radeon Pro 580X 8 Go
running Catalina 10.15.2
using Audacity 2.3.3
Also still struggling with it here. I moved to Catalina and having the same issues with 2.3.3. OS level had no impact (positive or negative) on the performance.
Hey!
I am having exactly the same problem with my Audacity. I am using Mac OS Catalina. Resizing window keeps lagging. Same as selecting parts of the wave.
Anyone found any solution for this?
Unfortunately still the case here as well.
Returning to Audacity after a bit of break from DJing and notice exactly the same terrible lagging when using anything other than a small window.
iMac 5K, 27", late 2015. 10.15.6 (Mojave), i5 3.2GHz, 16GB RAM
Audacity 2.3.3
Does that also have a high dpi display?
Hi all! I’m also having this performance issue. No external monitors connected
Laptop:
MacBook Pro (13-inch, 2019, Four Thunderbolt 3 ports)
2,4 GHz Quad-Core Intel Core i5
16 GB 2133 MHz LPDDR3
Intel Iris Plus Graphics 655 1536 MB
Built-in Display
13,3-inch (2560 x 1600)
Intel Iris Plus Graphics 655 1536 MB graphics
macOS Catalina 10.15.4 (19E287)
Audacity 2.4.1 (also tested 2.3.3)
I have the same very noticeable lag when using Audacity in full screen / big window, not happening on a small window. Did a short screen record that shows the problem,
https://www.youtube.com/watch?v=2KfDVXzTAdM
Thanks in advance
The current version of Audacity is 2.4.2. Updating is highly recommended as this is a bug fix release. https://www.audacityteam.org/download/mac/
Steve, do you know if 2.4.2 addresses this issue?
Also, the Mac page shows 2.4.1 as the latest release on 20 May. Is 2.4.2 now available?
Oops sorry, the sun must be getting to me 
.
I’m using Audacity 2.4.2, but it’s a pre-release version just for testing. The release version is 2.4.1, and that is the correct version that you should be using.
Apologies for creating confusion.
A “fix” was implemented around 10th May, so I think that fix should be in Audacity 2.4.1.
The problem appears to be due to a change in the Apple SDK which makes display repaints much slower. The Audacity developers have tried to work around the problem code. I would have expected 2.4.1 to be noticeably less laggy than 1.3.3. Is that not the case?
Ahh, OK! I was afraid I might not have seen it. 
I haven’t tried 2.4.1 but based on Masterl1nk’s comment earlier, it looks like the issue remains in 2.4.1. The performance on my machine is the same as what his video shows.
Installed 2.4.1 and the very laggy performance is still there, consistent with Masterl1nk’s observations. Did a clean reboot with Audacity as the first program open, etc. No change.
yes, the issue remains there. I have IOS Catalina. People posted a lot on this topic, but no clue yet, except for an advice to shrink the browser size to 1/4. It works a bit for my computer.
Same issue here (Catalina running on a Macbook Pro 16") and, incidentally, it’s causing some minor recording skipping as well.
I’ve found that changing my screen resolution to a lower setting improves the issue, although it’s still pretty bad. It’s not a great solution, but it beats working in a tiny window.
If I run Audacity in Windows using Parallels there is no issue with editing audio. I haven’t tried recording that way.
I had no problems on my 2015 12" MacBook. Strange that an 8-core beefy machine with an awesome graphics card can’t handle it. I saw in the documentation about recording skipping it saying something about high resolution monitors and redrawing the screen causing issue, and the solution is to shrink the window.
an 8-core beefy machine
I believe most of that beef is loafing. It used to be the case that Audacity is only running on one of the cores.
Koz
To everyone who has reported problems on this thread …
Please go to Apple menu > About this Mac then click “System Report”. In the system report, under Hardware, click on “Graphics/Displays”.
What do you see for “Framebuffer Depth”?
– Bill
There is a workaround that will make Audacity snappy again on 30-bit displays.
Right-click on the Audacity.app icon and choose “Get Info”. In the Get Info window, check “Open in low resolution”.
The GUI might look a bit fuzzy in places but Audacity will be “snappy” again.
– Bill
Thanks Bill! My 5K iMac is also 30-Bit as is my second screen. I tried the trick to open in low resolution and while it’s not “normal” levels of snappy performance, it looks very usable. I have a multi-hour edit job today and will see how it goes.
Thank you for the work-around!