That's probably because vsync still wasn't turned on (despite it being on in the driver control panel - it could be you were running skyrim in a window rather than true full screen - eg via Onetweak). The way to tell in game would be to display the fps (using either enb, MSI Afterburner etc), and if it caps to the monitor refresh rate, then vsync is on. The actual problem with game physics (and associated issues, including, weirdly, the sound of being underwater) is caused by an fps higher than 60. If vsync is turned on and there is no other fps limiter, the monitor refresh rate must be set to 60 hz (a higher refresh rate will still result in physics issues if the fps goes over 60 despite vsync being on). I have vsync turned off (in Skyrim ini and enb) but limit the frame rate to 60 using Bandicam (or MSI Afterburner, or the nvida/amd setting in the drivers). Keeping vsync off results in less stutters (but not completely since stutters in Skyrim can come from a variety of sources - loading textures, models, overloaded script engine etc).