I think the best way to answer this is to understand what is going wrong. What's causing the device to go wrong is that some sort of glitch--like a software bug, a hardware bug, an environmental glitch (power spike or drop), etc. has caused the system to be in a state that doesn't work. For example a software bug has overwritten the variable that tracks the number of players. or a hardware glitch where if the power drops for a millisecond or two, the DAC loses some sort of initial configuration.
So how do you fix that? Just turn the power off, then back on and the device will start back up in the initial, pristine configuration.

If you are into Dungeons & Dragons at all then it's definitely worth a watch.

McDonalds sells a lot of burgers but you don't give them any Michelin stars.

Maybe I should clarify my point then. Taylor series is the way pretty much every system (calculator, computer, cell phone, etc) computes a square root. You can look into the c stadard library and find the the sqrt funtion is implemented with a taylor series. This is because it is computationally efficient and provides a predictable level of accuracy. The estimation algorithm that every other person on this thread has mentioned is really only used by people wanting to do a manual computation, or as an exercise in an introductory computer science class.

You can use the average method to compute a square root, but the question was how a calculator computes it. That is definitely done by using a taylor series.

There is a mathematical concept called a taylor series that can be used to compute things like irrational roots. It is way beyond the scope of eli5. The basic concept is that you can repeatedly call this function and each iteration gets you closer to the real value.