Hi there,
have this problem too. High end system, settings maxed out, 3440x1440, frames around 35-60.
From time to time I get freezes, sometimes only seconds, sometimes up to 1 minute or longer! The sound continues and when the freeze is over, the aircraft is at the position it should be after the time. Pure luck it never crashed.
It happened at 2.5 beta/stable and now on 2.5.1 - no difference.
2.5 was a fresh install, I started playing DCS world with the beta-release of 2.5. Use a fresh Win10, no background stuff, a very clean system.
However I made one observation: I played about 4 weeks without TrackIR5 and never saw any freezes. Then I bought TrackIR5 and after 1 hour in the game freezing started. Could be coincidence, not sure.