Just now, tried powering up my Med500X2 but found it wont power on. Tried by #2 500X2 unit power adapter, powers up as normal. I guess, it is my power adapter being faulty. I'm residing now in China and trying to locate where to buy a replacement one. I found some adapter in internet, but it is rated 12V 3A and up. Will a 3A or 5A switching adapter work? Or will this overload my 500X2? Thanks guys...