There is a lot of interest in power delivery to the audio equipment. One of the "standards" has been the incorporation of an IEC connector, which allows the use of different power cords to power HiFi components.
There is a whole world of discussions about which cord is best, but we tend to forget that it's a long link that the power cord is part of. The least discussed item in this chain is the IEC female jack itself, which comes with the equipment and is rarely upgraded. People spend big money on exotic IEC plugs and neglect to check what they plug into.
You consistently find in the back of expensive equipment plain-vanilla off-the-shelf IEC female jacks with a fuse housing or integrated switch. These are generally machine-made with stamped metal conductors and crimped (!) metal-to-metal connections. Crimped as in metal pressed on another metal with possible air gaps that can arc or oxidize over time, not the best conductor technology... So, let's warm up the soldering iron and fix that overlooked problem!
Like anything else with electronic equipment - safety must be your very first concern!!!
You must disconnect the power and verify that all capacitors are drained before attempting any work on your equipment. If in doubt - seek expert help, and I don't mean an Internet expert, easily recognized as a fast typist with a busy keyboard, although there are exceptions. If you think that different power cords result in audible differences, you might be in shock when you find out what 20 cents of solder can do for you!
Pictures are of IEC female jack on a $5000 integrated tube amplifier. The first shows the back of the IEC connector as it came from the factory, the second is work in progress with two solder joints clearly visible on the right hand side. The dog hair adds realism to the whole story.