Hi @Shinya,
Thank you for your consolidated update, and all the additional information you’ve shared. I empathize with you on your frustrations with not being able to play audio in the sample rate you’re aiming to experience.
We were able to review a diagnostic report from your Roon Server, and here is what the logs definitively show:
The core failure chain is:
- Roon streams a 24-bit/192 kHz Qobuz FLAC track from
streaming-qobuz-std.akamaized.net
- The actual download speed consistently measures ~5,500–6,200 kbps
- Roon's calculated minimum required bandwidth for the track is 7,925 kbps
- The log repeatedly logs:
FTMSI-B-OE: poor connection kbps:5900 (min:7925) — the buffer drains, [prebuffer] sleeping in read -- this isn't good fires dozens of times per second, and eventually, Roon itself sends a stop command to the Linn, which then responds "status":"Stopped"
So the Linn is not failing on its own, Roon is stopping it because it ran out of buffered data.
Why some 24/192 tracks succeed occasionally: One track (the Florence Price Violin Concerto) hit 100% buffer and played fine, but its minimum required bandwidth was only 5,575 kbps. That’s a more compressible FLAC file (more silence/sustained tones). Densely-recorded orchestral music (like the Mahler) has less FLAC compression and needs close to 8 Mbps.
We’re also seeing a critical secondary issue, with frequent network disconnections: The logs show the IPv6 address changing constantly between reconnects. This triggers repeated NetworkUnreachable socket errors and Qobuz reconnects. These interruptions reset the TCP connection and force fresh range requests, which compounds the buffering problem.
The sustained ~5.8 Mbps cap is suspicious. If Windows TCP autotuninglevel is misconfigured or the receive window isn’t scaling: Throughput = RWIN / RTT
64 KB window / 80ms RTT ≈ 6.4 Mbps, which is exactly what you’re seeing
As a next step, let’s verify and fix TCP autotuninglevel. Open an Administrator Command Prompt and run:
netsh int tcp show global
Look at “Receive Window Auto-Tuning Level”. It should say normal. If it says disabled or restricted, that’s your problem.
To fix it, run:
netsh int tcp set global autotuninglevel=normal
If normal still limits you, try:
netsh int tcp show global
Then reboot and test.
With that, residential gateways can throttle HTTPS connections that look like video/audio streaming if “Smart QoS” or similar features are enabled in the router admin panel. Log into 192.168.100.1 and check for any traffic management or QoS settings and disable them.
We’ll be monitoring for your reply and results! 
