Finally rebuilt my MythTV box last week, retiring the original proof-of-concept underpowered system that had been, uh, proof-of-concepting for about 1.5 years.  Not that this is interesting to anyone, but I figured I should write some of the details down so that I don’t have to relearn everything all over again when I rebuild again in 2 years.

Also, I’m writing this post while not actually at my MythTV box so these details may all be wrong anyway.

Hardware

  • CPU:  Pentium 4 550 Prescott 3.4GHz
  • Mobo:  Intel D915GAV
  • CPU Cooler:  Rocketfish (Cooler Master 752 clone)
  • RAM:  3GB of random DDR (2x512MB and 2x1GB)
  • Storage:  4x120GB SATA I drives (3x WD, 1x Seagate)
  • Optical:  Some Lite-On combo CD-RW/DVD-ROM I salvaged out of a Velocity Micro system
  • Video:  ATI HD 4550 512MB
  • Analog Tuner:  Hauppauge WinTV PVR-USB2 external
  • Digital Tuner(s):  HDHomerun (QAM-256 modulation on both tuners)
  • PSU:  Soly-Tech 600W 24-pin thingy I had sitting around in a shrink-wrapped box
  • Case:  Some mid-tower, Idunno, if it’s not a Lian Li/Rocketfish I just don’t care

Total cash outlay for parts I did not get for free or have lying around the house:  $15.

Software

  • Mythbuntu 9.04 32-bit

Gotchas to remember for next time:

  • Mythbuntu is still retarded regarding HDMI audio, in that if the system is installed with a DVI-capable card (HD 4550) it will automatically assume that you must be using a 2-wire connector for HDMI audio, and will turn off all other mixer options.  I got around this accidentally by first trying it with the onboard DMA900, then installing the HD 4550 when the onboard evidenced tearing at 720p, without telling the OS anything.  Since it worked perfectly I did not screw around with it, although I know there’s a more elegant way to do this.
  • Likewise for the reported widespread problems with ATI’s crappy Linux drivers.  Never installed them.  Do not care about Compiz desktop effects on a system that will never see the desktop, which is XFCE anyway.
  • Fixed low ALSA volume output by setting maximum levels in 3 places:  internal MythTV mixer, desktop ALSA mixer (master and PCM), then via shell.
  • Categorize the PVRUSB2 as an IVTV MPEG2 encoder, just manually enter the /dev/video0 address and all will be fine.
  • Set options for the HDHomerun as a remote control receiver in the internal configuration menu (enable network remote control, change port) and in the hardware.conf, setting port and address and udp mode.
  • LIRC auto configs are nice but silly.  Take all of the resulting files out of ~/.mythtv and ~/ and actually build a damn file without using easily-corruptible includes, and then add the commands that are missing from irrecord.
  • For some reason mplayer did not like accepting remote codes through the HDHR.  After puzzling over this for about a day I took the easy way out, which was setting all players to "Internal" and using the default MythTV player.  This works fine on everything, with the possible exception of HD MKV files (still uncertain as it was stored on a USB drive).
  • Saving space on recordings is easy.  Default autotranscode is on, and default is set to Lossless, which saves almost nothing but is fast.  Set options for "High Quality" and "Medium Quality" as MPEG4 video streams, 2200kbps bitrate, resolution 1360×768 (HQ) or 720×480 (MQ), all other options as default.  Set the default transcoder by series rule, or for shows that have different potential inputs, by actual show.  HQ is only for HD recordings and it takes forever.  Very important to use the MQ transcoder on all analog tuner recordings as they are huge space hogs (2.2GB for 1 hour).
  • Almost all disk space is set as recordings space, in directories /var/lib/mythtv/recordings, …/recordings1, 2 and 3.  Set chmod to 777 on all and chown as mythtv:mythtv.
  • Set for daily mythfilldatabase runs with the option –refresh-all to keep up with weird changes.  Also use on-air guides as Poker After Dark tends to change its start time 2-3 times per day.
  • If I wanted to increase my cash outlay above $15, buy another NIC and slave the HDHomerun directly to it to avoid network congestion and packet loss.
  • Slaving on an external drive for video storange is annoying, and for some reason doesn’t always automount via fstab.  I remember having this problem before, but naturally did not write down the solution.  Just remember to add user,noauto to the options in fstab so the damn box doesn’t hang after post because a USB drive doesn’t spin up in 4 nanoseconds.

 

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