Re: [RFC PATCH 0/1] ALSA: add PreSonus Quantum PCI driver

From: Jamie Steele

Date: Sat Oct 24 2026 - 12:13:32 EST


On 8/20/26 4:36 AM, Nicholas Johnson wrote:

The driver provides playback, capture, raw MIDI, sample-rate control,
clock-source control, XRUN reporting, and surprise-removal handling.

Hi Nicholas,

I previously encountered sample-rate switching problems with this driver. Another Quantum 2626 tester has now reported similar behaviour using the August 20 RFC with Internal clock and direct ALSA hardware access, without PipeWire, JACK or a DAW.

His 15-minute 48 kHz duplex test completed without new xruns. At requested rates of 44.1, 88.2, 96 and 176.4 kHz, measured capture delivery remained around 48,000 frames/s. A nominal 10-second playback at 96 kHz took about 20 seconds. The actual hardware clock hasn’t been independently measured, so the cause is not yet isolated.

Full setup and results:
https://github.com/jamie-steele/presonus-quantum-linux/issues/34 <https://github.com/jamie-steele/presonus-quantum-linux/issues/34>

Is this a known issue, and is anyone already working on a fix? Is there a newer patch series or development branch available to test? I’d like to avoid duplicating work if an update is already underway.

Thanks,
Jamie