Why are digital streaming equipment manufacturers refusing to answer me?


I have performed double blind tests with the most highly regarded brands of streamers and some hifi switches. None have made any difference to my system on files saved locally. I have asked the following question to the makers of such systems and almost all have responded with marketing nonsense. 
My system uses fiber optic cables. These go all the way to the dac (MSB). Thus no emi or rfi is arriving at the dac. On top of this, MSB allows me to check if I receive bit perfection files or not. I do. 
So I claim that: if your dac receives a bit perfect signal and it is connected via fiber optic, anything prior to the conversion to fiber optic (streamers, switches, their power supplies, cables etc) make absolutely no difference. Your signal can’t be improved by any of these expensive pieces of equipment. 
If anyone can help explain why this is incorrect I would greatly appreciate it. Dac makers mostly agree, makers of streamers have told me scientific things such as “our other customers can hear the difference” (after extensive double blind testing has resulted to no difference being perceived) and my favorite “bit perfect doesn’t exist, when you hear our equipment tou forget about electronics and love the music”!
mihalis
Since I am receiving bit perfect signals nothing happening prior to the conversion to fiber matters IMO.
mihalis, that's the beauty of it.  With my WiFi computer noise, speed, amount of RAM etc. don't matter, but there is hardware prior to fiber and it does matter.  As long as you use the same hardware with different streaming providers result should be the same.
Its incorrect because its wrong. Your whole premise is false................Not only wires, I can tell the difference between lots of things- wire on the floor vs elevated, wire going one way vs another, warmed up vs cold, on springs vs cones, on and on. And on.
LOL.  Thanks for the facts mihalis and welcher.  Great discussion.
One reason might be that the distributor knows nothing, because some company like Foxconn designed and built it, and sells it to them to market.  Have you ever wondered why so many companies' televisions have stick on brand names.
It is not just electronics, either.  The new Supra is said to be made by BMW.  It is not, and neither is that BMW.  An Austrian company that designs and makes about 200,000 cars per year makes both, as well as the Mercedes G series, and others.  Like Foxconn with electronics, they design and make stuff, then sell it to other companies to provide drive trains, and then to market.  You can verify this by entering the VIN into your computer.  Also, the Toyota Sports car, that is the same car as the Subaru, has a VIN beginning with JF, for Subaru's  parent company, FUJI. 
German built cars built by BMW begin with WB.   W is for West, as in West "Germany".   Mercedes is WD (Daimler).  For vehicles made under contract for Mercedes,  ZA and KN are used.  If it starts with a J it is made in Japan, with numbers 1-5 in North America (USA 1-3).  The first letter of number is the country code. Who know who makes what anymore?
The Supra was designed by Toyota, using a bevy of BMW parts from the Z4, and ASSEMBLED by Magna Steyr. This is a contract manufacturing model that probably applies at least at some level, to much of the electronics industry at some level. Even Apple does not see value in setting up their own manufacturing lines.

That is much different from the model you are using with Foxconn where Foxconn sells it for rebadging. This is not contract manufacturing it is ODM (original design manufacturing). It does apply to some televisions, usually lower end models like Magnavox, RCA, etc., and perhaps some low-mid end models in other manufacturers, like Philips, but not to most of what you buy from say Samsung, LG, Panasonic.


I am not aware of any streamers in the audiophile world that would fall into the ODM category. That would be low end offshore DACs.
Jmphotography, in the system you describe there is no fiber optic blocking all noise and as a result I completely understand that there could be improvement with a good streamer. Thank you for that feedback.