Old Firmware - Why Sansa Clip Plus Shut Down While Playing?

Hello Sansa customers. I am not so recent owner of Sansa Clip Plus and today for the first time experienced player’s total shutdown while it was connected to iHome iHM60 portable capsule speaker:

After holding power button for half minute and pressing it again, the player worked. It was purchased in Israel and its firmware is:

V01.02.15P

The important questions are is it crucial to upgrade my current firmware to newer and is it possible to backup current firmware and later restore it in case something goes bad?

There’s very little difference between the firmware version you have (01.02.15) and the latest (01.02.16).  It won’t help prevent what you experienced. You did the right thing in resetting it. If it ever happens again, you’ll know what to do, but updating the firmware won’t stop it from occasionally happening again.