I've just bought the Hauppauge PVR-150 and I'm having trouble making it to work properly. I can't watch TV trough mplayer without getting an "Your computer is too slow" advice, and getting drops on the stream.

The funny thing is that I can capture TV without any problems using cat /dev/video0 > /tmp/test.mpg, and I can actually watch TV perfectly running:

$ cat /dev/video0 > /tmp/test.mpg
$ mplayer /tmp/test.mpg
both simultaneously.

I have already tried to build my own from the mplayer SVN, without any results.

Here is the mplayer output after a while:
MPlayer dev-SVN-r27056-4.2.3 (C) 2000-2008 MPlayer Team
CPU: AMD Athlon(tm) 64 Processor 3200+ (Family: 15, Model: 12, Stepping: 0)
CPUflags:  MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 1 SSE2: 1
Compiled for x86 CPU with extensions: MMX MMX2 3DNow 3DNowEx SSE SSE2

Playing /dev/video0.
MPEG-PS file format detected.
VIDEO:  MPEG2  720x480  (aspect 2)  29.970 fps  8000.0 kbps (1000.0 kbyte/s)
[VO_XV] Using Xv Adaptor #0 (NV17 Video Texture)
Opening video decoder: [mpegpes] MPEG 1/2 Video passthrough
VDec: vo config request - 720 x 480 (preferred colorspace: Mpeg PES)
Could not find matching colorspace - retrying with -vf scale...
Opening video filter: [scale]
The selected video_out device is incompatible with this codec.
Try appending the scale filter to your filter list,
e.g. -vf spp,scale instead of -vf spp.
VDecoder init failed :(
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffmpeg2] vfm: ffmpeg (FFmpeg MPEG-2)
Opening audio decoder: [mp3lib] MPEG layer-2, layer-3
AUDIO: 48000 Hz, 2 ch, s16le, 224.0 kbit/14.58% (ratio: 28000->192000)
Selected audio codec: [mp3] afm: mp3lib (mp3lib MPEG layer-2, layer-3)
[AO OSS] audio_setup: Can't open audio device /dev/dsp: Device or resource busy
AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample)
Starting playback...
VDec: vo config request - 720 x 480 (preferred colorspace: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.33:1 - prescaling to correct movie aspect.
VO: [xv] 720x480 => 720x540 Planar YV12 
A:  12.1 V:  11.7 A-V:  0.350 ct: -0.321 329/329 12%  6% 50.2% 65 0 

           **** Your system is too SLOW to play this!  ****

Possible reasons, problems, workarounds:
- Most common: broken/buggy _audio_ driver
  - Try -ao sdl or use the OSS emulation of ALSA.
  - Experiment with different values for -autosync, 30 is a good start.
- Slow video output
  - Try a different -vo driver (-vo help for a list) or try -framedrop!
- Slow CPU
  - Don't try to play a big DVD/DivX on a slow CPU! Try some of the lavdopts,
    e.g. -vfm ffmpeg -lavdopts lowres=1:fast:skiploopfilter=all.
- Broken file
  - Try various combinations of -nobps -ni -forceidx -mc 0.
- Slow media (NFS/SMB mounts, DVD, VCD etc)
  - Try -cache 8192.
- Are you using -cache to play a non-interleaved AVI file?
  - Try -nocache.
Read DOCS/HTML/en/video.html for tuning/speedup tips.
If none of this helps you, read DOCS/HTML/en/bugreports.html.
Thanks in advance.