Soix:
I have tried the exact same Linkup Ethernet cable from Amazon that you mentioned, in both a 5 meter long run from my router, and a short 1 meter run to my streamer from my Ether Regen. The cables look and feel very solid and well made, but they sound terrible! I gave them a couple of weeks use, just in case they needed to "settle-in", but nothing improved. They seem to suck the air/ambience and texture right out of my streaming system. A simple Cat 6 cable from Blue Jeans Cables for a similar price sounded FAR better, as did a higher quality DH Labs Reunion ethernet cable I recently purchased. And, yes, the sonic differences ARE apparent between various ethernet cables on a good system, despite what the naysayers claim.