Here's an interview with John and Anna, from Gamepadla:  A software-based input lag testing solution that also offers a hardware-test option for extremely accurate results.  I'm such a fan of any solution that makes lag testing easier and it would be hard to get much more accurate than this!  Please check out their website, both to download the software and try yourself, as well as to see current latency results:

Main Site:  https://gamepadla.com/
Creating The GPDL:  https://youtu.be/epm2li1hrK8Main
YouTube Channel:  https://www.youtube.com/@john_punch

...and if you're interested in how to run these tests using the MiSTer FPGA project, check out Louis' video, as well as the livestreams we did: https://youtu.be/6GGkVAi2db0 / https://youtube.com/live/sLsBhuJXpW0 / https://youtube.com/live/zhfk9GNFNWE

Please consider supporting this channel via monthly support services, tips, or even just by using our affiliate links to purchase things you were already going to buy anyway, at no extra cost to you: ⁠⁠⁠⁠⁠⁠⁠https://www.retrorgb.com/support.html⁠⁠⁠⁠

T-Shirts:  ⁠⁠⁠https://retrorgb.link/tshirts