Home Computer Audio Asylum

Music servers and other computer based digital audio technologies.

RE: Buffer update

I just completed the required setup to get DSD playback to work on my system.
I am using an old laptop (no ALIX, an HP Pentium M) running Fedora 19 and a Mytek Stereo 192 DSD DAC.
I also have other computers but I'ld prefer to use that old Fedora laptop as my music server since I don't need it for any other purpose (thus, it can reside at the stereo system all the time).

Principally everything works fine with that setup: I am using MPD (version 0.18.4) on the server and several clients (Theremin on the Mac, MPoD on the iPhone etc.) to control the music. However, when I play high-resolution files (Flac > 96 kHz or DSD) after about 1 minute there are glitches and
dropouts.

I already googled a lot on USB-dropouts and made the following plan, of what I'll try to do next weekend:

1) disconnect all other devices that are connected via USB to my laptop, such that only the Mytek uses the USB
2) plug a 2000mA-powered USB hub in between the laptop and the Mytek
3) increase the process priority of the music player (e.g. via "nice -n 10 mpd" on the command line) to keep it save from being interrupted by screen savers and the like
4) play with the buffering options (e.g. by putting period_size=50000 into mpd.conf - maybe someone has some more ideas here? What are good values for the audio_buffer_size and the buffer_before_play parameter?)
5) run some diognosys tools (http://wiki.winehq.org/MeasuringAudioLatency ) to check if there are DPC Spikes (if I find them: shouldn't the above two solutions solve this issue?)
6) run 'dmesg | less' to check whether there are enlightening log messages during the dropouts
7) upgrade the RAM of the laptop by plugging in new DDRs (the laptop has only 512 MB, but any DSF/DFF/FLAC file I tried should fit completely in there)

Do you have more ideas, what I could try?



This post is made possible by the generous support of people like you and our sponsors:
  Parts Connexion  


Follow Ups Full Thread
Follow Ups

FAQ

Post a Message!

Forgot Password?
Moniker (Username):
Password (Optional):
  Remember my Moniker & Password  (What's this?)    Eat Me
E-Mail (Optional):
Subject:
Message:   (Posts are subject to Content Rules)
Optional Link URL:
Optional Link Title:
Optional Image URL:
Upload Image:
E-mail Replies:  Automagically notify you when someone responds.