If you're having trouble changing to or from 2.4ghz/5ghz - where hitting apply has no effect, I have the solution.

Change the wifi to the frequency you want and THEN modify the NAME of the wifi, THEN hit apply. You'll lose your connection to the Spark and a new network with your chosen name and frequency will appear.

Not sure why you have to do it this way but it's the easiest way i've found to do it.

If you're having trouble changing to or from 2.4ghz/5ghz - where hitting apply has no effect, I have the solution.

Change the wifi to the frequency you want and THEN modify the NAME of the wifi, THEN hit apply. You'll lose your connection to the Spark and a new network with your chosen name and frequency will appear.

Not sure why you have to do it this way but it's the easiest way i've found to do it.