The Bad - Occasionally, perhaps once every 10-15 switches between computers, either the keyboard or mouse would be unresponsive.  This was corrected by simply switching from the non-responsive PC to a different PC and back.  While a minor annoyance, this is a behavior I had never seen in a KVM before. It is evident when Computers 1, 4 & 5 are in use. This issue COULD NOT be replicated when computers 5 & 6 were connected to the KVM.  An intermittent problem that only occurs on my PCs, and not Snicker's is hard for me to say 100% that it is a flaw of the KVM.  It may be, it may not.  Belkin had no suggestions for this issue when contacted. 

A second issue popped up when a computer was connected via the PS/2 ports.  If the mouse had a scroll wheel (which the tested ones did - MS Intellimouse, and MS Intellimouse Explorer v.3.0), if you moved the mouse during the 1-1.5 second lag that occurs when switching from one PC to another, a mouse wheel input was sent to the computer, which resulted in your screen scrolling or other action attributable to a wheel input.  This problem has only recently started to occur, in fact, prior to going to Snicker's house to try to reproduce the first annoyance, and the video issues discussed below, I had never seen it happen in 4 weeks of product use.  The workaround fix is to simply connect to the KVM using the USB port as I have not seen it happen unless the computer was connected via the PS/2 port. 

The Ugly - There were a few video anomalies noticed when connecting the KVM to computers 1, 5, & 6.  Essentially, images were being ghosted a bit on the display, and on computers 1 & 5 a diagonal distortion was visible intermittently.  The distortion was more noticeable when connected to the KVM via a 10 foot monitor cable, yet when connected via a 4 foot cable, the distortion was virtually non existent.  Belkin responded to this concern by shipping the 3d Retreat new 10 foot cables.  The new cables were nickel plated, whereas the original cables were gold plated.  I tested all four new cables and while the distortion was significantly reduced both in magnitude and frequency, it still existed to some degree.  The distortions were much less pronounced and I could no longer photograph the distortion with my digital camera.  

Conclusion

All in all the Belkin 4-port PS/2 / USB KVM w/Audio is a very nice product. The minimal footprint, and space saving cable management design are heaven-sent for someone with a messy workspace such as myself.  The addition of audio (both speaker and microphone) capabilities to this KVM product really set it apart from the competition.  It is extremely nice to have the sound follow you from computer to computer as you switch amongst your connected PCs (or macs/sun stations if you swing that way). 

I attribute the video anomalies experienced to the ten foot vga cable length.  The distortions were intermittent and almost non-existent on four foot cable length.  The mouse and keyboard issues experienced were also intermittent, we couldn't reproduce the one error, and the other can be worked around by only connecting via USB.  This tells me that if it is even an issue with the KVM and not something with our system configurations it can likely be fixed with a firmware upgrade down the road. 

For anyone that has a need for a 4 port KVM I would definitely recommend this product because it works, and the addition of USB/AUDIO/ and Belkins unique cable management system put it a leg up on the competition.