NVDA automatically switches between synthesizers when I have more than one configuration profiles. For example, If I have set One Core as my synthesizer, then NVDA will automatically switch to Espeak when I interact with my Windows and related applications. It goes back to One Core when I’m interacting with NVDA settings itself, reading a document or while browsing the internet. The situation is similar with any synthesizer set as default. And, I can observe this same issue on NVDA 19.2.1 installed on my system and NVDA 20.1 which I sometimes use as a portable version. I reported the issue once on this list and was told by someone that the code for configuration profile is buggy. It would be great if you could help in any way.