This morning I had discharged my 2017 MBP 15" base model down to 40% running Windows 7 in Vbox and a few office apps+ Skype. I put it on the bed and connected the charger. Came back with my coffee after 10 minutes and the machine was really hot on the bottom center! Scary hot. I took it off the bed and placed it on my knees but I had to avoid the center since I couldn't have it touch my skin. My old 2013 MBA with the same apps running while charging never got this hot! I then started a Skype session, audio only and went on with it for 30 minutes. Despite sitting with air underneath and not really starting any windows programs in Vbox etc but just checking email and doing a Skype call it didn't cool down until it had recharged completely. So I stopped at a Best Buy and ran the dev null tes command starting 4 processes on a 13" and 8 on the 15". Let the battery go down 10% while I ran some apps like FCPX and Garageband and iTunes playing songs. After 15 minutes I reconnected the chargers and none of them (15" was actually a 2016 model) got any hot at all, barely warm underneath. Btw,my CPU never went beyond 40% as far as I could see from Activity Monitor while the two machines at Best Buy were at 100% CPU usage while i was testing them. Now this has me worried. Could there be something wrong with the battery/charge mechanism in my MBP? I have scheduled a Genius appointment at the end of the week and I am still in my 2 week return period but would prefer not to have to replace it since I think the keyboard is great. No stuck keys even though it ran this hot for 30 minutes so it passed that test real good! Has anyone else felt such heat from underneath their MBP while charging?