I hear a clicking/slapping noise only when I am on the treadmill. Does this mean it needs to be tightened?

worn put parts inside, need to be serviced
all machines on earth do that,

Bad bearings torn tread belt slapping under load?

Did you ever get an answer back for your question? I just received my 9700 Pro in late March 2015. After only 4 times using it I also have the clicking coming from the drive motor. It sounds like the motor bearings.

I think my friend, you should look towards getting your engine replaced. If you hear like a clicking or clunk noise while you drive, the internals of your engine are worn out and hitting against each other.
Your options are:
1. Scrap car or sell it
2. Swap engine for a new one
3. Get the engine reconditioned

Error 22 means the drive motor is diconnected. you will hear the fan and other parts make noise but check the red and black anderson connection between the main circuit board and motor.

Typically you can tighten the belt with an allen wrench at the rear of the belt, treadmill be sure to align belt before tightening. Alternate each side as you tighten

It sounds like you have a bearing failing, either in the front roller or the motor. If it is the front roller it will be a dull "Clicking" noise, if its the drive motor it will be a growl noise. The growl will be so loud at top speed you wont be able to even talk over the noise. Remove the motor hood and this will help you determine the culprit.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/matt_8dbc24bf722649ac

This is more than likely a loose drive belt, which would explain the slipping as well as the sound. To tighten this take off the plastic cover that covers the motor. You will see where the motor connects to the front roller with the drive belt. To tighten it there are two bolts that hold the motor to the machine, loosen those then pull it tight and retighten them, This should eliminate the problem.

raise the incline and look under where motor is and spray some silicone lubricant on all the piston like things.

where did you buy the unit. you still be under warranty. noises are funny sometimes, you think it is hear but then its over hear. There will be noise fron under the belt that is normal. sometime it is louder in a house then in a store. you may need some waxon the deck as well. culd be plastic rubbing in the belt.

I’m happy to help further over the phone at https://www.6ya.com/expert/howard_079189dd4959a511