My fridge is making a machine gun sound as it refills the water for ice maker/water dispenser?

SOURCE: Amana SBS Water and Ice maker issues

The water solenoid on the back of the refrigerator at the bottom is becoming clogged. There is only a very small hole in the diaphram of the valve. I suspect you have very hard water, or at least a fair amount of sediment in the water.
This valve will most likely need to be replaced by a qualified technician.
They sometimes can be cleaned, but it doesn't always work.

SOURCE: amana side by side ice dispenser leaking water

icemaker wont dump ice

SOURCE: amana ice maker not working

From your description, would it be likely to assume that you are experiencing a water pressure issue? If so, then I would start the investigation at the supply valve that attaches to your homes water lines and do whatever is best for you, i.e. replace the valve or attempt to disassemble and inspect it for blockage. Once that has been removed from the list of suspects, the next culprit is your water inlet valve on the refrigerator. This has filter screens and can become blocked by water residue. These can be removed and cleaned or you can replace the valve to completely eliminate any other electrical/mechanical aspects of the valve. Below is a link to assist you in finding parts and diagnostic tips.
http://www.repairclinic.com/SmartSearch/smartsearch.aspx
Tip: Always provide the complete information provided on the manufacturers product information data tag, located on the unit, and not in the user’s manual. This will help you acquire a more accurate and expeditious response to your complaint.

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Thank you,
Dave E. (Illeagle)
"Your satisfaction is my personal reward"

SOURCE: Neff K3990 Fridge Freezer ice maker not working and water leaking out

Sounds like the water hose to the ice maker has come loose. Is it in warranty?

SOURCE: Amana Side-by-Side Fridge Model SBD21VPSE

If there is a reset button on your ice maker try pushing it. Many ice makers have two holes for reset. A general rule of thumb is if the ice maker fingers are stopped in a slightly vertical position then your ice maker unit is working. If the fingers are stopped anywhere else then it needs some sort of attention or replaced. Make sure there is water, or ice in the ice maker tray, if not then the problem is with water supply.