I'm also having the same issue - as you said, placing the laptop on a slanted surface makes this much worse. Levelling the body/keyboard surface quickly alleviates the issue for me, but sometimes it's still a little problematic.

Do you (or does anyone else) have any idea what could be done to fix this?

Hi @Aayush_Pandey0000  & @cbutcher welcome to this user to user discussion forum. This is not Dell Support. 

From your description the bearings in the fan have failed and possibly running dry, having lost lubrication. This is a well known m15 R2 problem [Here] [Here] [Here]. 

The remedy is to replace both CPU and GPU fans, because the other fan may have the same problem and having opened up the laptop, replacing both fans is easy. 

Dell Support for Alienware m15 R2 Service Manual Removing the fan and heat-sink assembly is not particularly helpful because it describes replacing the whole heat-sink assembly and not the fans. Guess this Service Manual is intended for users that have a Dell warranty or extended warranty and this assembly is not available on many external vendors that provide new Dell OEM parts. 

The fan plate can be removed and replaced [Here] but access to both sides of this assembly on the system board (aka motherboard) is required, for fan plate, screws and electrical cable.

The next question is where to get the m15 R2 replacement fan plate or fan or upgrade? Internet search says get cooling fans N18E part number 0X9FRW, but these look different. The m15 R1 cooling fans also look different. Perhaps another user can provide clarification. Or if you are suitably miffed, take the laptop apart to get fan specification and then get an improved quality replacement. @DELL-Cares 

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