My Alienware 17 R5 came with (according to the manual) a Thunderbolt 3 connector on the back and a USB Type-C port on the side.

Absolutely nothing works as it should in either of these ports.  If I plug a mouse in the mouse judders and lags.  If I plug my headphone in, I get the occasional blast of maximum volume in otherwise medium volume.  If I plug an external hard drive (WD My Passport) in, sometimes it shows up and sometimes it doesn't.   These two ports are absolutely useless to me and I don't know how to fix them.

I have searched the Dell site for answers, have ensured I have all the latest drivers, have flashed the BIOS for most recent version.

I am down to using the 2 old fashioned USB ports with a hub and I am very disappointed.  Does anyone have some words of wisdom for me?