Keys keep breaking off our wk-3000 this start just after we bought it brand new in austboughtrial we brought it back to new zealand and have put in 4 new sets

Question moved from Cars and Trucks to a Casio Keyboard one.
Easy enough if you can find the part.

https://www.google.com/search?q=casio+wk-1250+parts+diagram

casio WK1250 Parts and Accessories - PacParts

https://www.pacparts.com > model > model_id=WK1250
Mfg / Model No, Description, PDF, Year. casio WK1250, Musical Instrument: Electronic Keyboard, 1998. The following parts are available for the model listed ...

Casio WK-1250 Repair Parts and Accessories - Syntaur

https://syntaur.com > keyboard > keyboard=2080
Casio WK-1250. Released in 1998. The WK-1250 is a 73-note consumer keyboard with built-in speakers. Synth. All photos are copyrighted by Syntaur, ...

Casio Keyboard Junkyard: Welcome

https://casiokeyboardjunkyard.com Used accessories, parts and stuff for Casio Keyboards ... CASIO WK-1200, WK-1250, WK-1300, WK-1350 models are basically the same and use the same parts.

Casio Repair Parts - Keyboard Kountry

https://www.keyboardkountry.com > keyboard-parts
Casio Repair Parts ; Yamaha Brand Key Lube (Small). $3.80 ; Casio CTK-560L Ma1M Light Boards. $9.95 ; Replacement Keys for Casio CTK-491 and Others. $10.95.
Missing: 1250 ‎' Must include: 1250 ..

You bought the wrong model - e.g. Yamaha models work reverse.
Return for Exchange
Or try opening up and re-solder the cable to the micro switch if possible

Make sure you are using NAME BRAND alkaline batteries that are in date. Rechargeables will NOT work in these.

Check the neck to body attachment. There may be a problem there, especially if it has been strained in the past. The fact that the strings were so high when you got this would indicate there MAY be a problem with the neck attachment or the body where it attaches. Word of caution: Investigate how repairs are done on the instrument before attempting a fix. Using wrong materials can permanently disable an instrument. Banjos DO go out of tune easily, depending on how they are played. Another thing to remember is that strings are within about 10% of breaking when in tune on stringed instruments.

You have to get a cable that runs from the 1/4 inch headphone jack on your keyboard to the 1/8 inch line in on the back of your iMac.

It sounds like the sustain is stuck on as if a sustain pedal is active. You don't mention if you have one, however if you MIGHT have one and you have used a Roland pedal, that brand is reverse sensed and would cause note to remain on.

The adapter required is a 12 volt 1.5 amp (1500ma or 18 watts). Check the polarity carefully as to whether the pin or the shell is positive... Many Casio have the shell as positive but do NOT gamble, check for the markings near the connector.

The keyboard has a mic jack that is the same size as the headphones. You probably put the headphone plug into the wrong jack is all.

No.

I have a Wk-8000 & a CDP-200R, the later is the same as wk-500 but with 88 weighted hammer keys.

Since wk-500 can play SMF (Midi 0 & 1) format directly from a SD card and there is enough polyphony to play anything, I don't find any real reason to convert SMF to any "Casio Format". Just get a 2GB SD card and put your SMF files in the MUSDAT folder for the SD CARD using your PC/MAC.

I had the same problem. You might try the keyboard on good fresh high quality batteries. If this solves the problem, buy another ac power adapter. Good luck!!