Does successively turning power on and off damage an Arduino or Adafruit Audio FX Sound Board in long or short term?

I build a "fairy phone" out of an old rotary phone, an Arduino Pro Mini 3v3/8Mhz, an Adafruit Audio FX Sound Board and a rechargeable battery.

In an attempt of being clever, I reused the handset holder as on/off button switch. What I did not take into consideration is that kids not only have fun playing with the rotary dialer, but also with the handset hangup buttons. As a result, arduino and soundboard are toggled on/off often and in short cycles.

Is this somehow bad for the devices? Should I add an capacitor to bridge over short on/off cycles? I never write to eeprom, AFAIK the Sound Board does not write to it's memory in playback mode.

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    Turning on and off any electrical device is the moment when it survives the highest strain. Coils (even ones that are just tracks on a board) induce highest EM fields, capacitors (even ones that are just "virtual" ones inside transistors) take (or give) highest possible current. It's never a good thing to turn something on/off very rapidly. Even MOSFETs will burn faster when they are used in PWM circuits. The oldest working light bulb on the planet was only turned off few times. en.wikipedia.org/wiki/Longest-lasting_light_bulbs – Filip Franik Feb 18 '19 at 9:33
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    I guess the "clever you" was outsmarted by your kids :-) – Gerben Feb 18 '19 at 16:52
  • a capacitor would help take the edge off, literally. You might need to also cap-up reset for stability if the edge gets too gradual. – dandavis Feb 18 '19 at 20:35
  • @Gerben it took him 5 Seconds. Of course I didn't give him the breadboard prototype but the finished, soldered device. Doh! – dube Feb 18 '19 at 22:37
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    @dandavis you can do the same trick on arduino (is't it just a RC filter on the reset pin?). Note that the they already use the 65ms startup delay (set in the fuses of the AVR). – Gerben Feb 19 '19 at 12:03

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