Strange "No input" error from LG 34UC97

Hello all,

I just bought a LG 34 inch curved monitor to use as a desktop replacement for my Macbook pro 13" retina laptop. I was so excited! The monitor is beautiful!

However, to good to last, on the second day of use it started to go blank after a few minutes of use, and a "No input" would come up on the monitor screen. This occurred when I had the macbook hooked up via the thunderbolt cable (brand new) after a few minutes of use. There didn't seem to be a pattern of timing when it would happen. If I unplugged the thunderbolt cable and plugged it back in, it would start working again for another few minutes.

It didn't matter if I turned off the "sleep timer" for the macbook, or weather the macbook was in clamshell mode or open. The macbook was not going to sleep. I tried restarting the computer and monitor, no help. I tested it in a guest account on my mac, no help. I "chatted" with apple support and reset something (I forget what) by holding the control/option/shift while restarting. I also tried the HDMI cable, which did a similar thing, except it didn't give the error, the screen just turned off and on after a few minutes.

I think it is a monitor problem, as I plugged it into my iMac desktop and it did the same. I tried using the HDMI to a different monitor no problem.

Sorry to posting on an apple site, but I called LG support, who were terrible. Within thirty seconds of me being on the call they insisted this monitor was not compatible with apple despite it being advertised as "for mac" on the box, and having 2 thunderbolt inputs. Very unhelpful.

Does anyone have any ideas before I return this beautiful monitor?

Thanks!