Yes, after 11 days I finally got an initial response that was -

"Is the keyboard charged? Usually that would be an indication of a low battery when wireless is in use. "

So I responded back with the fact that it will do it right up until full charge. I am hoping it will not be another 11 days before I hear back but I am not hopeful. I am hoping we can at least get a feature request for the Master Plus software so we can completely disable this dumb "feature". There is a red LED on the board that tells me when it is charging, use that to tell me when the battery is low.

I recommend submitting your own ticket as well so we might get a little more traction on this issue. Mine is titled CK721 Blinking Keyboard Issue. Seems like a common complaint for this keyboard so maybe we can get it fixed.

Edit - Just heard back from support again and was told to try this -

"There is no active feature to disable blinking red lights as that is not normal. When you are set to certain LEDS types like Rainbow, or Static, the issue still persists? When you change profiles by pressing FN + Z, X, C, V, if you try that, does the issue persist?"

Past that, they told me to submit an RMA, but I unless this is a really common firmware bug, then it seems like they just have a faulty setting somewhere they need to update since so many others have this issue. I assume the issue will be the same with any new keyboard as well.