Allo Boss Stuttering with anything 352khz and over

Apologies if I am posting this in the wrong place, I am a total newbie on this forum (but not to audio!).

I just setup my Rpi 3 and Allo Boss on the latest release of Volumio. It is running off a linear power supply, and is connected to a USB through a powered hub. The music is playing off the USB.

I am getting stuttering on anything playing above 352khz, I’ve tried playing with the settings in playback options, but I can’t seem to get an improvement.

Any advice would be much appreciated.

Hey All,

Just wanted to add that the files are M4A. Don’t know if that changes anything.

I believe the 384KHz limitation is hardware related to the RPi’s USB port (the internal design of the BCM283X USB interface) so its data B/W limited.

This is not related to the RPi design but the method the USB interface is implemented within the BCM283X processor.

We use the CM3 module (basically a RPi3) and have found anything upto 384KHz stable - but you know you are very much pushing the hardware limits at 384KHz.

Thanks, that’s valuable insight.

My chain from USB drive to Rip USB input has a few jumps that could be an issue, I’ll check them out before I recompress everything to a lower Khz.

The Pi USB bus is known to often be causing issues. The Pi has a single USB-otg port and I guess in your use-case, the heavy reading it has to do over the USB bus to read these very high bitrate files cause interrupt problems on the Pi and in turn cause buffering issues in the I2S output.

Try putting a high-res file on the local SD card and see if that plays without issues.

Verzonden vanaf mijn iPhone met Tapatalk

I discovered the problem for future reference.

I am powering the unit with a linear supply I built, it measures perfectly, but I got lazy and used a USB micro cable to connect the supply. As it turns out the wire gauge in the cable was not high enough to carry the necessary current. I bought a raw usb micro connector and used a decent gauge wire, and it works perfectly!

listening to 384khz 32bit right not.

Thank you for your help!