Problems when using the PVR-350 encoder

[sore]

I recently installed mythdora and MythTv is now running ok, but I have a performance problem. I have a PVR-350 and when trying to use the oncard encoder ("use the PVR-350's TV out / MPEG decoder") I get the error below. Without this setting it works ok, but the image is not really good.
Can anyone please help??

2006-05-04 07:43:07.877 Connecting to backend server: 127.0.0.1:6543 (try 1 of 5)
2006-05-04 07:43:07.888 Using protocol version 26
2006-05-04 07:43:07.909 TV: Attempting to change from None to WatchingLiveTV
2006-05-04 07:43:07.924 Using protocol version 26
2006-05-04 07:43:08.230 RingBuf(/video/recordings/1049_20060504074308.mpg): Invalid file (fd 17) when opening '/video/recordings/1049_20060504074308.mpg'. 12 retries remaining.
2006-05-04 07:43:08.731 RingBuf(/video/recordings/1049_20060504074308.mpg): Invalid file (fd 17) when opening '/video/recordings/1049_20060504074308.mpg'. 11 retries remaining.
2006-05-04 07:43:09.309 Opening audio device '/dev/dsp'.
2006-05-04 07:43:09.309 Opening OSS audio device '/dev/dsp'.
2006-05-04 07:43:09.318 NVP: Enabling Audio
2006-05-04 07:43:09.333 IVD Error: Framebuffer number query failed.
			eno: Invalid argument (22)
			Did you load the ivtv-fb Linux kernel module?