DSP Upsample Static

Hi Everyone,

I have a Pro Ject Pre Box S2 Digital connected via certified USB 2.0 to my 10th Gen NUC i7 with 32GB RAM running rockOS. This issue I’m having has been ongoing for at least six months now and I can’t get to the bottom of it. I have DSP enabled to upsample Max PCM rate (power of 2). Generally, when I start playing an album encoded at 44khz/16, I’ll hear static over music. I have to toggle off Sample Rate Conversion, let the track resume, toggle SRC back on and I’m good to go. There’s no issue with bandwidth, I’m still processing at about 8x and can upsample to DSD512 without this issue. That’s the first part of the problem. The next part is when I switch albums, if it’s in a different format (say 96khz/24), the static is back and I have to do the same thing all over again. This only happens when upsampling to PCM, like I said, upsampling to DSD causes no issue. I’ve tried resync delay, buffer adjustments, different USB cables, different software builds, firmware checks on the DAC, this issue even persisted when I was just running Roon core on the NUC, before converting to rockOS. I’m at a total loss here. I have no clue what’s causing it and would like to be able to continue upsampling PCM…

Hi @Tyler_Kemp ,

Apologies for the slow response here.

What happens if you don’t upsample to a power-of-2 but just do Max PCM without power-of-2? If you downsample from 96/192 to 88.2 or 48, does the static occur then too?

Have you tried a different USB port or USB cable? Did those also reproduce the issue? Since it’s working with other sample rates it doesn’t sound like the cable could be the issue, but worth a check just in case.

Hi @noris the static occurs regardless of upsample to max rate or power of 2. It does not occur when downsampling. I have tried a different USB cable and different port as well.

Hi @Tyler_Kemp ,

Do you notice this upsample distortion while using other apps to upsample as well? I recall I had a case in the past with this device and a few users reported similar behavior, see here:

It’s only when using Roon. It’s only when I initially play a file. If I get distortion, switching off Sample Rate Conversion (without pausing playback) and then switching it back (sans pause) resolves the issue 100% of the time. If I play a file encoded with a different sample rate, I have to do the same thing. It’s basically like I have to reset something every time a new sample rate is played back.

Hi @Tyler_Kemp ,

Can you try to adjust the Resync Delay in the Devie Setup and check if this helps?

I’ve tried all different settings in there to no avail. It doesn’t seem like a buffering issue since as soon as I toggle sample rate conversion off and back on, it proceeds immediately without issue.

This topic was automatically closed 45 days after the last reply. New replies are no longer allowed.