I purchased two VMS4 , and I also have the Hercules RMX unit . So whenever I hook my Chauvet LEd h20 into the same power bar , If I turn off my LED H20 Light , it will shut down my system . Now I did some test , and this only happens with this light . So I took it back to the store and exchanged for a new one . Yes the same thing happened . So I tried it with my other VMS4 unit , and yes the power went off again . So I did some more test , I hooked up my Hercules unit , and then turned off my light... it did not power off my system . Now this only happenes when I have the usb hooked up with the vms4 . I put my vms4 in anolog mode, just used it as a mixer , and used the sound card from the laptop . The system did not shut down my sytem when i turned the light off . Now I can do one or two things , I can keep the light on all night , or run to another seperate outlet , only problem with this , is sometimes to get to a seperate outlet in a hall you need to run a Extention sometimes 100 ft away . Anyways if you guys want to do a test for me and hook up your vms4 , and if you have a Chauvet led h20 light , hook it up to the same power bar , and turn off the light . Let me know what happens . Any other observations please let me know .