It's possible the version control extension is involved, yeah. We've seen that once or twice in the past. (e.g. Extensions which keep trying to contact a network server for version control information.)
You can use ShellExView to see which extensions are installed and selectively disable them to see if it solves the problem. With this type of extension, it's best to fully exit Opus and then restart it after enabling/disabling, as the extension may already be loaded in the process when you make the change. (You don't need to reboot the whole system or anything like that, though.)