Review on StarTech.com 4 Port USB DVI KVM Switch with DDM Fast Switching Technology and Cables - Enhanced Four Port DVI USB KVM Switch - Dynamic DDM KVM Switch (SV431DVIUDDM) by Reginald Ward

Very unreliable. First I toggled the sound and then stopped interacting with the sound completely. The only way around this problem is to connect the speakers directly to my main computer, leaving other computers with no audio output. There is also often confusion when switching videos. It does not tolerate systems trying to use different monitor resolutions. After forcing all systems to use the same monitor resolution I thought I solved this problem but no. It still happens to be hanging on one of the running computers with no video stream. Turning KVM on and off didn't help. To "fix" this, I had to manually disable and re-enable the video stream for that computer. This product isn't very useful if I have to constantly manually disconnect different cables to get it working. Unfortunately, I kept the thing for so long that I can't return it now. I strongly advise others not to buy this so you won't be disappointed. It's not worth the trouble.