Are manufacturer AC cables good enough?

I forgot Andorra. How about Andorra? 🇦🇩 

FWIW, the Marantz CD6006 CD Player is a good example of double-insulated equipment. As shown (link below), the IEC socket does NOT have a ground pin and the double-insulated logo (square within a square) is displayed in the Marantz box near the middle of the pic.
  
https://www.us.marantz.com/en-US/shop/hificomponents/cd6006#gallery-3

nsgarch:No, disconnecting the ground conductor at the EQUIPMENT end, as I specified, does NOT create a safety hazard.  However, disconnecting the ground conductor at the wall outlet end does indeed create a safety hazard!  A bit of research into equipment grounding techniques will explain why"

You are confused, uninformed, and ignorant regarding the nature of electricity, electrical circuits and grounding the defeat of any safety ground most positively, absolutely, and definitely without exception creates a possible, potential, "looming" safety hazard the result, consequence, and outcome of which can be deadly. I suggest you consult your Boy Scout handbook and look up definitions for "open circuit" and "closed circuit" and then report back.

You all must be talking about window unit air conditioning cables. 
I have central air and it's on a dedicated line directly from the breaker box.
Perhaps if you guys ran your window units off a dedicated circuit it might alleviate any quality issues you may be having. Just a thought...