RiscOS USB Audio
Brett Rogers (9204) 5 posts |
Hi All, I’ve got RiscOS Open running on my Pi400 and I’ve got it plugged into my monitor via HDMI but my monitor doesn’t have any speakers so I’ve got a USB Audio device plugged into it. I was wondering if there was any way i.e editing the config.txt file to get the USB audio working or forcing USB audio. Usually I’d go to Raspi-config and change it to USB Audio as default but I’m not sure how to get to there when loading RiscOS up. I’ve looked at many other threads but wasn’t sure if there has been any more movement on it. Kindest Regards, Brett |
Raik (463) 2031 posts |
Hi Brett, |
Jean-Michel BRUCK (3009) 282 posts |
Your monitor may have a headphone output ?, I use mine this way with an external amp. Colin created an application that allows you to play audio files to a USB device (DAC) A very interesting site for RISC OS audio: |
Andrew Rawnsley (492) 1423 posts |
Colin’s isochronous drivers (which allow for USB audio) only work on USB2 ports on Pi. On a Pi4 that means the USB-C port and things connected to it rather than the rear ports, all four of which are XHCI-connected not EHCI (USB2). I fear the Pi400 ports are all on the XHCI controller too, but I may be wrong on that (I don’t have a 400 set up right now). |
jim lesurf (2082) 1399 posts |
Colin’s progs are a good way to check if your choice of hardware will play/capture via USB Audio. If they show it will, it may also be useful to try the prog I wrote that both outputs audio and re-captures it. That can check for any problems like noise, distortion, etc, to see if it works as it should. In particular, can show if your choice of USB DAC or ADC is delivering good quality conversions. |
Brett Rogers (9204) 5 posts |
Hi All, My Monitor doesn’t have an audio out it’s purely a display monitor. No sound on it at all. Just for clarification the USB device is plugged into the USB on the pi400. Thanks, Brett |
Andrew Rawnsley (492) 1423 posts |
Honestly, your best bet if you want to use a monitor without speakers with a pi is to use an HDMI audio extractor which can be bought on amazon for less than 20 ukp. They’ll take the HDMI feed, and split out the audio into analogue or spdif (depending on what you need), and work with both RISC OS and linux. On RISC OS, even if you managed to get the USB device to work, it would only be utilised by specific player software (WAV, FLAC, MP3) – general OS sound and games would not make use of it. |
jim lesurf (2082) 1399 posts |
The snag with going via HDMI is that that may modify the actual stream of audio sample values. Depends on what monitor/devices you have, etc. Probably won’t matter if you just want ‘games’ beeps and bangs, etc. But if you want to play high quality audio it might affect results. You’d need to decide/test/check specs if you want to ensure what comes out of the setup. What USB device do you have, and what kind of audio do you want to hear? |