Xcode Test without building will hang indefinitely until timeout when using pre started simulators

So some of our test containers will randomly hang until our timeout limit (60mins), this happens randomly with it affecting a different container/job every time and only on some workflows

We use pre started simulators as we were having issues with CircleCI not being able to find the simulators we wanted when using Xcode 10.1.0

Any ideas what could be causing this issue/how to resolve it?

Heres a screenshot of what the failed job looks like for reference: