Theres a loud squeaking noise when the mixer turned on

That green sparking looks to be in the area of the off/on contacts, look for something causing them to not be touching properly. The speed control lever has a ramp on the plastic end that goes through that speed control plate to move that copper arm, that is the off/on switch. I'm wondering if maybe the voltage from your converter is not fully as it should be, just a thought. If you wanted to properly convert to Euro voltage you need an armature, a set of fields and that small PCB with the 6 wires off it just above the black speed control plate. You set your slowest speed (#1) with the 2 screws and locknuts on the top of the speed control plate. 13 to 15 rpm in 15 seconds, I do it by running mixer with palm of my hand in position to be bumped by the silver shaft on the planetary each revolution, count them and watch your second hand. Once that is done you set that bottom screw to just increase the speed as you click the lever into speed 2. Had a look at your video, the governor does not sound happy, it could be the back plate adjustment out of whack to cause it. You can email me with more questions if you like [email protected]

It's gonna be the generator! When you hear this noise it's deffinately the generator

It sounds like the Worm Gear is going out. The faster the motor runs,
the more damages the Center Gear is grinding away the teeth of the
Worm Gear. Things start to slow down, and eventually they will come
to a halt. It's time to replace the Worm Gear. Also make sure to use
new fresh Kitchenaid Food Grade Grease with the new replacement.

I had your same issue with the speeds. I think you need to adjust the speed through the speed control panel.
Open the back spherical cover on the Kitchenaid KSM90, the area with one screw on the top. You should see the speed control panel, a black and gold square connected to wires. There should be three large silver screws - two on the top, left and right - and one on the bottom. If you turn the top two screws clock wise the machine slows down at lower speeds. When you adjust the bottom screw, the higher speeds are effected. This process is called "tuning" and you can find an online video how-to through sites like Youtube.
As for the squeaking, you maybe replace some of the grease inside of the machine. Food grade gear lube would do if you are up for the challenge, but kitchenaid also sells a grease for their stand mixers for a pricey $20. It isn't hard to put in new grease and clean out the old but requires a lot of disassembly.
~ I am not an expert but a hobbyist. This advice is only my opinion based on limited experience. ~

I don't have a direct answer for you. There are many things which could cause the noise from a beater simply hitting the bowl to internal gear problems. You did not say which model you have so take a look at the two Service Manuals linked below. One of these ought to cover your machine.

http://www.kitchenaidparts.eu/documents/pdf/service-manual/classic-svc-manual-new-email-version.pdf

http://ep.yimg.com/ty/cdn/mendingshed/kitchenaid6qtservicemanual.pdf

See the Service Manual:

http://ep.yimg.com/ty/cdn/mendingshed/kitchenaid6qtservicemanual.pdf

I strongly suspect that this is a gear problem.

Diane,

It appears that you've got some internal transmission gear issues, and a situation similar to my wife's mixer, which we got new in Dec 2006. It could be as simple as the gears have become loose and are making different contact, hence the noise. The higher the speed, the louder, higher pitched sound you'll get. It may also be indicative of a potential gear failure (after all our increasing noise, the bevel gear broke and the mixer 'froze'). If your mixer is under warranty, contact Kitchenaid. If it's out of warranty, then take it apart and do a diagnostic exam of the gearing. Whatever you find you should be able to fix yourself. Be sure to have the Kitchenaid Part Manual (Part No. 8212278 Rev D) on hand if you attempt to disassemble yourself. It also lists all the parts so that you can determine, which parts, if any have failed. You'd think that the Kitchenaid name would warranty their mixers for a lifetime... but alas they do not. So much for quality in America today!

lgardash, Are you sure it's the motor or could it be the transmission?
It 'sounds' like you've got some transmission gear issues, and a situation similar to my wife's mixer, which we got new in Dec 2006. (Within a week of her first using it, she contacted KA Customer Care and the only 'care' they offered was an explanation that the new KA Pro Mixer gears are all metal and to expect it to be louder than previous models that used a plastic gear (to fail). Well, there's an acceptable level of noise, and an unacceptable level (you don't need to be a mechanical engineer to know when something doesn't sound right) and it seems that my wife's new mixer's operating noise level was always unacceptable. It finally 'died' this past October.) OK I've vented enough on KA... now what might be your problem(s)?
It could be as simple as thorough normal use the gears have shifted slightly in the transmission and the gear teeth are making different contact, hence the grinding/squeaky noise. The higher the speed, the louder, higher pitched sound you'll get. Alas, the noise may also be indicative of a potential gear failure (after our mixers increasing noisiness, the bevel gear broke and the mixer 'froze').
If your mixer is under warranty, contact Kitchenaid. If it's out of warranty, then take it apart and do a diagnostic exam of the gearing. Whatever you find you should be able to fix yourself. Be sure to have the Kitchenaid Part Manual (Part No. 8212278 Rev D) on hand if you attempt to disassemble yourself. It also lists all the parts so that you can determine, which parts, if any have failed. You'd think that the Kitchenaid name would warranty their mixers for a lifetime... So much for quality in America today!
I hope this helps, and good luck! - Howard, Burke, VA

It appears that you've got some internal transmission gear issues, and a situation similar to my wife's mixer, which we got new in Dec 2006. It could be as simple as the gears have become loose and are making different contact, hence the noise. The higher the speed, the louder, higher pitched sound you'll get. It may also be indicative of a potential gear failure (after all our increasing noise, the bevel gear broke and the mixer 'froze'). If your mixer is under warranty, contact Kitchenaid. If it's out of warranty, then take it apart and do a diagnostic exam of the gearing. Whatever you find you should be able to fix yourself. Be sure to have the Kitchenaid Part Manual (Part No. 8212278 Rev D) on hand if you attempt to disassemble yourself. It also lists all the parts so that you can determine, which parts, if any have failed. You'd think that the Kitchenaid name would warranty their mixers for a lifetime... So much for quality in America today!

Unfortunately, the Kenmore mixer sounds louder than freight train due to a poor planetary gear design. I had to take mine back so that the neighbors wouldn't **** me. I hooked up two identical models at the store to get the same, painfully loud, experience. I think I prefer the sound of a bandsaw to the grating noise it produced.