When I connect the MacBook to the monitor via USB-C, it is fully charged and in sleep mode, the 100% battery icon with the power chime comes on approximately every 60 seconds. I can't figure out how to turn off the charging sound. It must be the monitor, because it doesn't happen directly from the adapter. So for hibernation I have to switch off the monitor (then the MacBook doesn't charge) or shut down the PC directly completely. Anyone got any ideas?