Interesting! And welcome to the community! What version of RStudio are you using? And is this the pro or open source version?
One good way to figure out what is going on is to look at the output of:
sudo lsof -bT -p `pidof some-parent-process`
For some parent process. i.e. rserver, etc. Finding out where all of these file descriptors are at will be useful to isolating what the problem is.