Galaxy S5 :: Intermittent Freezing On Phone

I recently had intermittent freezing on the phone -- in apps (new and old), on the lock screen, on the launcher. After searching the Web, I did everything recommended--numerous soft resets, a couple of hard resets, consulted Samsung's technical chat room, took the phone to Samsung's local kiosk for a forced software update--nothing worked and the end result was that Samsung said it was a hardware problem and that I needed to send the phone in to Samsung for a look at the hardware. Before doing that, I looked at the system and saw that it did not show any storage information for the SD card. I replaced the SD card and it fixed the problem--the phone is operating just fine. It would have saved me a lot of aggravation if somewhere along the line someone had thought to look at the SD card -- apparently a bad SD card can cause system instability on the S5.