I just update x-plane 11 to beta 11.50. I realized the SSG 748 V2 has no engine sound either inside the cockpit or outside.

Yes, it is X-Plane BETA and the problem is known. You can find a workaround for now (on your own risk and I would make a copy of the package to do anything) in the org forums.

hey thanks for the answer

My pleasure! Enjoy!

how do I fix mine ? how do I find a walk around?

I also have the SSG V2 and the sound is not working can you please help me