To check for updates using Sansa Updater, you do not need to switch modes. The updater works with MTP mode, which is the default mode right now on your device. You do not need to change to any other mode to check the updates. The only suggestion for you is to download the right Sansa Updater v1.082 at the following link: http://www.sandisk.com/Retail/Default.aspx?CatID=1376. Now, before you do this, please uninstall the current updater you have on your computer, restart your computer, then install this new updater. Then when you connect to your PC, you will see a small icon “S” on the bottom right side. Click on that and choose to check for updates and it will pop up the screen. If there are updates, then the “Firmware” will be blue. If there are no new updates or your player has the most current firmware, then the “Firmware” will be grey. If you want to understand what is the difference between MTP and MSC. I can give you a little head up.
MTP = media transfer protocol, which works well with Window Media Player where you can sync songs, playlists and transfer DRM or subscription contents through these vendors: Rhapsody, Napster, Yahoo, etc.
MSC = mass storage capacity, works like a USB or thumb drive. It displays as a drive under your window explorer when you can drag-n-drop things in the device just like how you just drag-n-drop files into your thumb drive. However, it does not support DRM content transfer meaning that if you use your device in MSC mode, then you cannot transfer subscription music.
As for the step that you did, the “Press & Hold” option under Setting is not MSC. It’s the option to allow you to choose what you want to do when you press and hold your center button. For example, if you select “Press & Hold”, it gives you the option to “Add to your GoList”, “Rate Song”, etc. You can choose one of those options and then when you playback your music, you can just press and hold the center button to have it “Add to your GoList” or “Rate Song”. It’s just like a short cut so you don’t have to browse through the whole setting just to get a song added to your playlist. Hope this clear you up on some of the questions you have. If you have other questions, feel free to ask.