How to reset? - Casio Privia Px-130 Px130 88 Key Digital Stage Piano Nu

Question edited for clarity.

Try a Factory Reset. Try a power reset first. Disconnect from the mains plug for 15 minutes.

System Reset - Yamaha PSR-S750 Service Manual

ManualsLib https://www.manualslib.com > ... > Service manual
There are two reset methods in the SYSTEM RESET display: Factory Reset and Custom Reset. ... This function lets you restore the status of the instrument to the ...

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  Yamaha PSR-S750 Reference Manual - System Reset

  https://www.manualslib.com > ... > Reference manual
  This function lets you restore the status of the instrument to the original factory settings. ... buttons to enter or remove the checkmark. ... operation for all ...
  
  

Question edited for make model (what it is)
Question moved from Cell Phones

Factory Reset, or Hard Reset doesn't clear ROMS

https://www.sweetwater.com/sweetcare/articles/perform-simple-hard-reset-factory-defaults-kurzweil-k2000-k2500/#:~:text=On%20the%20K2600%20or%20K2661,powered%20off%20and%20back%20on.

More here

https://www.google.com/search?q=kurzweil+k2600+reset+ROMS

and here

https://www.google.com/search?q=kurzweil+k2600+format+ROMS

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Have you ever changed the internal Lithium Battery. Try the reset here, although it is for a different model. The Keyboard was actually made by Casio and sold with the Radio Shack name on it.

REPLACING THE MEMORY BATTERY

Your keyboard uses one lithium battery to protect some types of data when it is turned off. This battery is installed at the factory,
and lasts up to 5 years. If the keyboard's memory is erased when you turn the keyboard off, take the keyboard to your local Radio Shack store to replace the lithium battery.

RESETTING THE KEYBOARD

Note: Resetting the keyboard clears all information you stored in the keyboard's memory, including the parameter settings, song
sequencer, pattern sequencer, and registration memory. Resetting the keyboard's parameter settings clears only those settings from
the keyboard's memory. To reset the keyboard, turn the power off.
Then hold down ENTER. Reset? appears. Press YES.

https://www.google.com/search?q=Radio+Shack+Midi+Keyboard+MD-4072+reset

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Here's a video showing you exactly what to do! https://www.youtube.com/watch?v=HXFN0LymD0Q

To reinitialize the IS-SPX-1000 unit to its factory default settings:
1.
Unplug the unit from the power.
2.
Push the reset button and keep it pressed.
3.
Power up the IS-SPX-1000 unit.
4.
Wait with the reset button pressed for at least 8 seconds.
5.
Release the reset button.
6.
The IS-SPX-1000 unit will now boot in the factory default mode.v

It's possible to reset the DTXPRESS electronic drum kit to its factory default settings by performing a Factory Reset. Here's how you can do it:

Press and hold the [DRUM KIT] and [SAMPLE] buttons while turning on the power switch.
The display will show "FACTORY RESET OK?"
Press the [DRUM KIT] button to execute the factory reset.
The display will show "INITIALIZING" while the reset is being performed.
When the reset is complete, the display will show "COMPLETED".
Note: Performing a factory reset will delete all user kits, samples, and other custom settings that you have made. Be sure to save any custom kits or settings that you want to keep before performing the reset.

To perform a factory reset on the Zoom R16 recorder, follow these steps:

1. Power off the Zoom R16 by pressing and holding the [STOP] button.
2. While holding down the [STOP] button, press and hold the [REWIND] button and the [PLAY] button.
3. Continue holding all three buttons for about 5 seconds until the display shows "Factory Reset."
4. Release all three buttons and the unit will automatically restart and restore all factory settings.

Note: Performing a factory reset will erase all user data and settings, so be sure to back up any important data before proceeding.

Reset Instructions:
1) Try a partial reset by holding down the last white key while turning the unit ON.
2) If you haven't recorded any performance(s), for a full reset, hold down on the last white key AND THE lst three black keys while turning the unit ON.

You may need to do a factory reset. It sounds linke a transpose setting has been invoked. Read your manual under the word "transpose". A factory reset, if required, usually involves holding one or more buttons or keys down while turning on power and holding them until the reset is acknowledged.