Connecting Denon surround amp to laptop

[vdgg]

Hello everyone,
Hope I'm posting to the correct forum.
I have a new (used) Denon AVR-X1300W amplifier that I'm connecting to my laptop (over Thunderbolt docking station), to play surround musing over HDMI, and I'm facing a strange issue that some of you may have the solution to (I wasn't able to find a solution) - if the laptop (Windows 10) boots when the amplifier is already on - I can see the DENON-AVR as a sound output device and everything works great (mostly). If the amplifier is turned on after windows is already up and running, it doesn't recognize it as a sound device (but I do see it as a display device).
If it matters, I defined the amplifier as a display device.

Any help would be appreciated.
Thanks.

 

[vdgg]

Just in case anyone in the future finds this while having the same issue, drivers updated using Windows Update have resolved the issue (when the amp turns on, the audio device is detected on the fly and I can play back normally).