Random sound quality & ASIO audio stream path

Connection with external Audio Devices
1

My setup is the following one:

PC with Windows 10 and Audirvana 3.5.3

Synology NAS

TEAC UD 503 DAC

Raspberry 4 bridge

Sometimes the sound quality is just stunning: each instrument sounds really sharp and alive with a 3D texture/energy, the dynamics and sound stage are incredible. The sound is so good that the band could be playing live in front of me, beyond the speakers. I believe this is when the Bitperfect/ASIO audio stream transmission is taking place. I get this kind of incredible sound from time to time.

Most of the time the sound is OK but doesn’t come close to what I have described above. The bass and imaging are a bit muddy and I have the feeling that the audio stream transmission is not bitperfect at all. Could it be possible that the ASIO driver is not used? Does Audirvana bypass the DAC’s driver to use its own??

I’m really puzzled by all of this because it is extremely frustrating, with the feeling that I can get much better I also often get error messages about the playback peripheral being unavailable, or A+ stuck to loading the first track with nothing happening after that. Am I doing something wrong? Is there a specific sequence to turn devices on? I never know which device I shall reboot (Raspberry, NAS, DAC, computer) before it works. Could it be the reason why I sometimes get superb sound quality and average quality other times?

And one last thing: I have installed a Raspberry endpoint that is correctly detected by Audirvana but how does this configuration handle ASIO drivers?? Does Audirvana use the DAC’s ASIO driver to transmit bitperfect data from the PC to the Raspberry endpoint? I’m really curious about the way Audirvana handles audio streams in different configurations as I couldn’t find any documentation.

2

Is your PC dedicated as a music server, or is it a general purpose computer used for many different things ? the computer electrical environment may be changing time to time, so the sound quality. Same thing with power supply, at night you may find the sound better just because there is less electric pollution on the public electricity network …

3

ASIO is relevant for the playback through USB. Audirvana streams to the RPi bridge using UPnP. Try putting a switch between the RPi and the router. Even better a slower fast ethernet switch.

4

Yes I use my PC for multiple purposes, not only music. Do you think a difference of electrical quality could make such an impact at playback level??

5

I guess so, audiophile often start with their general purpose PC, then use a dedicated one to play music (many use a Mac mini in this forum …) and the ultimate solution is a music streamer optimized for audio only, with embedded SSD, streaming capabilities, etc …
I also noticed that a WIFI router placed very close to your PC will impact sound …
You can check your task manager when the sound is bad, and check memory or CPU usage …