I would suggest to start with, try using some other browsers and see if the outcome is any better or different.
If not, you are welcome to try our latest beta and see if that gives better results. You can download the installer here: https://download.shedworx.com/jaksta/beta/3.0.0_315/JakstaMediaRecorder.pkg
When you first attempt to run the installer you will receive a Mac OS notification saying that it can't be opened because it cannot be checked for malicious software. Click 'OK' and then go to System Preferences > Security & Privacy > General and click on 'Open Anyway' down the bottom. It will either run the installer or another similar notification as the first will appear and you just need to click 'Open' and then the installer will run.
It's important to keep in mind that Twitter and Instagram are highly likely to have features in place that block what Jaksta and similar applications do. Considering their resources and technical ability it would be very unlikely that we would be able to get around it.
Hey over the last few months Ive been having issues recording from instagram and twitter. I'm currently using safari.