MacBook Air won't sleep with display/ethernet connected

hi,

I have a wierd problem with my Air (11" 2013 model).

Usually at home I'm using it with external monitor (HDMI), closed lid and USB Ethernet adapter.

I send it to sleep with the apple menu sleep option, and it looks it goes to sleep, there's no

signal on the monitor, so I disconnect the power from the socket.

If I don't disconnect the thunderbolt and the usb ethernet, the battery percentage is around 87-88%

in the morning, which means the Air is awake for at least hours.

Power nap is disabled. tried with 10.9.1, 10.9.2.

Appreciate any advise.