HELP! several issiues with both my DAC_I and mkIII

[Azide Fox]

I'm kinda new to the whole audio community so excuse me if its just me not know what im doing.
Anyways lets start with how I have it set up right now PC(USB) -->little dot DAC_I (RCA)--> little dot mkIII (RCA)--> Stax SRM-252s amplifier --> Stax L300 earspeakers.
Lets start with the volume adjustments. When I have the DAC_1 hooked up the volume settings in Windows(10) stops doing anything even if its all the way down to 0 it still plays music just fine? (This happens even if the amp is not hooked up).
I have another problem with the volume adjustement too. When I was using my AKG K702 via the headphone jack on the front of the mkIII it was impossible to adjust the volume anywhere, it was at a constant max.

Now back to using the Stax again.
The problem I have with the mkIII is that it doesnt seem to be doing anything except lowering to volume quite significantly (I can still achive a good listening volume but its very close to maxing out). I dont even have to have the amp powered on to get a signal through it and when I compare the sound it makes when its powered on to when its powered off I cant make out any precivable difference in either quality or volume. So what in the world is up with that? I even tried switching places of the RCA outputs to the inputs and vice versa and I still got a signal through.

Like I said im not sure if there is something wrong with my unit or im just being an noob at this stuff (I bought both the DAC and amp from amazon uk if thats any help)

[rockage]

Take a good, long look at your connections.

[Wilsonnuare]

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[Catillbew]

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