Powerful core PC can't upsample to DSD128 in Roon

My i7 4790k/4Ghz PC can upsample 16 or 24bit files in Roon to PCM384 no problem. The processing speed of the PC while doing this (from Roon Signal path enhanced box) is around 7.0 when converting a 14/44 or 24/96 file.

However, when trying to upsample 24bit files to DSD 128, the processing speed drops sufficiently to cause playback to stutter, cease and jump to next track after 45 seconds of playback. I have recorded the following Processing speeds:
16/44 to DSD128 Processing speed: 2.3x (Runs OK but stutters occasionally)
16/44 to DSD64 Processing speed: 3.0x (Runs OK but stutters occasionally)
24/88 to DSD128 Processing speed :0.9x (Runs for 45 secs and drops out completely)
24/96 to DSD64 Procesing speed: 1.4x (Runs for 45 secs and drops out completely).

The system is as follows:
Computer: Intel i7 4790k cpu 4Ghz and 24GB Ram.
BT hub/router
Running into a Netgear FS108 switch
Hardwired to Sonore MIcrorendu
feeding a T+A Dac8 dac.
I am running the latest version of Roon and I use both Tidal and USB storage connected to the PC. The issue is the same when using Tidal or stored files.

I would have thought that my PC was more than capable of upsampling to DSD128 (I haven’t even attempted higher sampling rates). Any help much appreciated. Thanks.

Have you checked “Parallelize Sigma-Delta Modulator” under the sample rate conversion options?

Every single piece of soft have to be laboriously and meticulously optimised…

Thank you for the post @Audio_John and sharing your feedback with us. The insight is very appreciated!

I agree with @rob2’s suggested in making sure that "Parallelize Sigma-Delta Modulator” is enabled in the sample rate conversion field. Additionally…

  1. Have you tried reinstalling the driver for the DAC8?

  2. In the “playback” settings window in “device setup” have you tried enabling “work around drivers…”?

  3. If you have any DSD 128 content in your library have you verified what the experience is like playing back one of these files and temporarily bypassing the DSP engine?

  4. Have you verified what the experience is like if your shorten the chain of communication and then play directly of the PC via USB the DAC8?

  5. By chance have you taken any Win10 updates recently prior to noticing this behavior?


The 4790k is a 2013 Haswell cpu, has anyone else had success with it upsampling to DSD?

I am using an i7 5930K, which is the Haswell-E and benchmarks pretty close to the i7 4790K.

For upsampling 16/44.1 to DSD64 I was getting a Processing Speed of 3.3 and no drop outs (that’s in line with your 3x)
Reading this thread, I set “Parallelize Sigma-Delta Modulator” to ON and the Processing Speed has settled at 6.1 (balanced setting on PC).
Performance setting is currently at 8.2x and heading north, so I’d say there is 2.5 to 3 times improvement through simple settings changes.

I have an i3 4th gen it’s fine upsampling to DSD128 processing speed is about 3.5 X which is adequate and that’s without parrelizing sigma Delta.