Question on my DAC


I have an ARC LS27 preamp and recently bought a used Bryston BDA-2 DAC which improved sound quality significantly. Oh so satisfying...
However, I have a question about sampling rates: I stream music from Deezer and the new Amazon HD streaming service. It seems no matter what I stream, including remastered recordings etc, the sampling rate stays at 44.1Khz. There is also an LED that indicates it's "locked".  I can push a separate "upsampling" button, but the lock remains in place and also stays at 44.1KHZ. I don't see any "unlock" buttons and the user manual doesn't give a lot of information on that subject.  My source is a Bluesound vault and I use the coax output.
Again, I love the sound this thing produces so I'm not searching for better quality, just curious about how the sampling is supposed to work.
Thanks!
128x12861falcon
The "lock" indicator on the Bryston DACs is to show the DAC is synched with a digital input. It's unrelated to the specific sampling rate.
If you were to play true high res offering from either Amazon HD or from Deezer, you would see the Bryston DAC lock in at something greater than 44.1 kHz.   So for example, if you were to play MQA offering from Tidal via your Bluesound Vault, you would see your Bryston BDA-2 lock in at rates up to 96  kHz.
When I go to Amazon HD or Deezer, I see no indication as to what the sound quality should be. Is there a way to identify this on their app.?
Thank you!
I have the same issue with my Rega DAC. Think it has something to do with DRM (digital rights management). I tried to feed it from BluRay media and only got the low sampling rate. Really bummed me out...
I finally got it to sample at 96KHZ after I found a "legacy" recording in Amazon. I wish these streaming services would be clearer on what exactly the sampling rate was. It doesn't appear there are many recordings above the 44.1 KHZ level. Comes across to me as misleading. 
Post removed 
MQA will give you 96
That’s what it does on my BDA-1
I’ve gotten 192 on Qobuz
A lot of stuff that says HR on Qobuz locks at 44
Regular files also lock at 44
The HI Res may be 24bit instead of 16, I have no way of telling
Qobuz will do 24/192
Deezer is 16bit FLAC. Have no idea about Amazon
I wish Amazon would mark the files. There is no indication of the sample rate
I’ve never seen anything above 44 on Deezer, but I’ve only had it a short while
Just my brief observation, only had the DAC a week or so
Up sampling does not change the sampling rate on the front of the DAC
The manual has the up sampling info
you can get some free samples at hdtracks of 24/96
when you play a digital file on the pc regardless of the vault the player(winamp or whatever you use) should indicate the sample rate
try to contact the seller ask him about it
is it possible not to use coax? try another input(usb,optical) 
the vault and bda2 are really nice products that should play up to 24/192 with no problems.hope this helps