UPDATE 7/21/2013: Several people previously had trouble with this post due to confusion over WordPress’s annoying automatic smart quotes substitution. I’ve figured out how to disable that behavior now, so all examples should be used exactly as shown. Also added info about newer versions of VMware and host operating systems. Anyone that uses on Windows and on the Mac together with a screen reader has probably noticed that the screen reader’s speech doesn’t respond quickly when they press key commands. Since a common behavior of screen reader users is to rapidly skim through information by repeatedly pressing a screen reader’s navigation commands, the slow response of the screen reader’s speech inside a virtual machine means that the guest operating system seems sluggish.
Reset the System Management Controller (SMC) if your Mac shuts down when you plug in an external hard drive. Then use a different port to connect the external hard drive. If you’ve got a battery that you can’t remove: Shut down and unplug the power adapter. Press Shift-Control-Option and the power. I am running Windows 7 inside Mac OS X with VirtualBox, I used a BLE inside W7 without any problem. Then I used the BLE USB in the Mac, and when I try to use it again in the W& I got this message.
Background vmWare provides sound output for the guest operating system by simulating a virtual sound device inside the virtual machine. In the host’s operating system, vmWare uses sound in a similar manner to any other application. The vmWare application is, therefore, a proxy between the virtual sound device and the actual sound capabilities of your computer.
Since vmWare is an application, it has to compete with other open applications for your computer’s resources. If multiple virtual machines are open, those virtual machines are also competing for limited resources. If the resource needs of an app other than vmWare, or another virtual machine, experiences a sudden spike, vmWare might temporarily be unable to pass sound between the virtual sound device and your computer’s physical sound device. In this situation, sound output from the virtual machine could seem to pop and click, or sound output could briefly stop altogether. To improve this situation, vmWare buffers sound between the virtual and the physical sound devices. A buffer is an area of the computer’s memory that holds a fragment of information (sound, in this case).
When a virtual machine plays sound, instead of passing sound directly between the virtual (guest) and physical (host) sound devices, the guest side of the connection places sound in to a buffer, the buffer is first allowed to fill with sound data, and, once the buffer is full, the host side begins to remove sound information from the buffer and pass it along to the physical sound device. Under normal conditions, the guest side will keep the buffer full by placing new sound information in to the buffer only as fast as the host side removes sound information. If the computer’s resources suddenly become limited, the guest side might not be able to continue placing new sound in to the buffer, but the host side can continue to remove and play sound that has already been accumulated in the buffer. Once resources are available again, the guest side can catch up by quickly placing new sound information in to the buffer until the buffer is full again. A similar process happens in reverse when a virtual machine records sound from a physical sound device. The buffer prevents brief shortages of computing resources from causing pops and clicks in the sound of the virtual machine, but it also places all of a virtual machine’s sound on a delay.