Are you just experiencing this behaviour with ANA2 only or do you have other issues as well with other plugins in FL Studio ?
If you're using the latest ANA2 version and the 32bits VST only according to your system, it could very well be that this issue is not coming from ANA2.
You have to make sure that you are using your system & FL Studio at their best in order to troubleshoot this correctly.
Depending of your PC specs, DAW & audio Interface setup, many things could play a role and lead to such behaviour.
It could help to go to Win Task Manager , find the matching FL.exe process and set it's priority to 'high' as well as stopping unnecessary tasks & apps running in the background.
In FL Studio preferences as well you can try to adjust audio & buffer settings.
Maybe this could help you to check those and troubleshoot more to be able to say that this is coming from ANA2.
( Link is not active, copy/paste it into your browser )