What could be reason behind sound in stick shift?

I have a manual transmission Liberty. I took it in when I heard what sounded like fluid rushing through the stick shift shaft. The repair shop put a new transmission in. I still heard the sound and took it back. They removed the new transmission, put in new bearings and put back together. I still hear the sound of fluid. While I plan to take it back again, I thought I would ask what the problem might be as I know nothing about cars. Just super frustrated at this point that after 3 weeks and thousands of dollars, the problem is not fixed.
Thank you for your input.