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...