Ethernet cable comparisons - a few thoughts

Must admit I hadn't given ethernet cables much thought until recently, apart from wanting to replace a few cheap ones I bought/got with other things where the retaining clip has broken.  I have a mixture of cheap cables (including from places like Home Bargains for a quid) and named cables from the likes of Belkin.  A variety of Cat 5/5e/6.

Logically my brain tells me they shouldn't make the slightest bit of difference if the same data is getting through.

If there is a difference is it due to packet errors/resends that eventually get through or other timing issues, 'mysterious' noise brought into the streamer or some other undefined quality?  Afraid I'm at a bit of a loss here.

A few things that have come to mind tonight testing a few demo cables:

1 - Could be placebo effect naturally.

2 - Does unplugging/replugging ethernet cables just clean the connectors as I could have sworn the bog standard cable sounded better after reconnecting it having listened to a different one!  Then again how would this affect things if the signal is getting translated into digital data and the data eventually gets through unadulterated?

3 - Timing - some manufacturers blurb mentions timing errors (yes superficially sounds feasible) but when I thought about this it's not as though you have a digital transport device feeding a DAC at a fixed rate (I assume they do) - the network will presumably offload the streamed file from a NAS to the streamer far more quickly than the track is played - i.e. we're not talking about real time data transfers that may be affected by subtle timing errors as the streamer will presumably have cached the file to play within a few seconds of getting it from the NAS - so if the file is cached in the streamer how does the ethernet cable affect the sound for any duration longer than the track takes to stream unless it's reducing some kind of noise introduced into the streamer's circuitry and the data transfer is secondary?

4 - Is ethernet cable length a determinant of any kind?  Is a 0.75 m cable better/worse than a 5 m cable from the same manufacturer?

5 - Most suggest placing the cable at the last hop in the network to the streamer to give best improvement irrespective of cable type up to this point from the NAS source.  How can it correct what went before?

6 - Cable direction - again supposedly a factor and another variable to A/B for a given cable.

7 - Testing methods - it occurred to me that if I streamed a track, swapped cables and listened again that without knowing the precise way the streamer works it would be possible that the track is still cached and played as if from the previous 'session' unless you somehow flush the cache by playing other tracks or maybe a power down.

8 - Probably already done but have people compared streaming audio files over ethernet vs the same files stored on locally attached media?

9 - I'm sure I had some kind of lightbulb moment of insight but nodded off and have now forgotten it! Hopefully it will come back to me.

Sadly (or not) despite all this scepticism, after trying a single 'audiophile' cable I was stunned by the difference from the basic one I'd hooked up before - I told the family I was testing something and to shut their eyes - within a few seconds they all said the second play of a track sounded louder, more controlled in terms of bass, warmer and generally more detailed which was precisely what I thought myself (non-blinded to the tweak) - admittedly I had the audiophile cable the wrong way around but if it sounds better the correct way I'm yet to A/B!

Sorry to detract from the other ethernet thread currently but wanted to see how others do their A/Bs and raise some of my thoughts above.  Something is still eluding me.....