I've had nothing but problems with Apple's "Power Nap" functionality. I remember three discrete issues with my 2014 MBP (Quartz would randomly crash out of naps when connected to external displays, the topcase frequently felt mysteriously warm and my media controls would freak out forcing me to close spotify/firefox before closing it) Ironically, the only time I've seen it behaving as-intended was when I had my T460p running MacOS with photo analysis disabled. I'm guessing it's an ACPI issue, since Apple's track record with the technology is shaky.