cx88x sound

Well I’ve been trying to get suse 11.x up on antec media center and run mythtv on top of the platform. Only one thing “partially” missing is the sound. I hope that I’m not annoying anybody by posting this on the wrong site but hopefully somebody will give my directions on that or if there are something that I forgot to mention.

I’m lost here and I hope somebody has the same problem and a solution to this problem !

Problem. Mythtv, xawtv and tvtime all display picture close to 100%. Sound start as 100% ok but after 30s - 100s gets lot of white noise in it.

tv-card:
TV-card. Hauppage wintv-hvr-1300

kernel :
Linux linux-afeq 2.6.34.4-0.1-desktop #1 SMP PREEMPT 2010-08-20 19:21:29 +0200 x86_64 x86_64 x86_64 GNU/Linux

pci devices :
00:00.0 Host bridge: Advanced Micro Devices [AMD] RS780 Host Bridge Alternate
00:01.0 PCI bridge: Advanced Micro Devices [AMD] RS780 PCI to PCI bridge (int gfx)
00:04.0 PCI bridge: Advanced Micro Devices [AMD] RS780 PCI to PCI bridge (PCIE port 0)
00:0a.0 PCI bridge: Advanced Micro Devices [AMD] RS780 PCI to PCI bridge (PCIE port 5)
00:11.0 SATA controller: ATI Technologies Inc SB700/SB800 SATA Controller [AHCI mode]
00:12.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0 Controller
00:12.1 USB Controller: ATI Technologies Inc SB700 USB OHCI1 Controller
00:12.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI Controller
00:13.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0 Controller
00:13.1 USB Controller: ATI Technologies Inc SB700 USB OHCI1 Controller
00:13.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI Controller
00:14.0 SMBus: ATI Technologies Inc SBx00 SMBus Controller (rev 3c)
00:14.1 IDE interface: ATI Technologies Inc SB700/SB800 IDE Controller
00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA)
00:14.3 ISA bridge: ATI Technologies Inc SB700/SB800 LPC host controller
00:14.4 PCI bridge: ATI Technologies Inc SBx00 PCI to PCI Bridge
00:14.5 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI2 Controller
00:18.0 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor HyperTransport Configuration
00:18.1 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Address Map
00:18.2 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor DRAM Controller
00:18.3 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Miscellaneous Control
00:18.4 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Link Control
01:05.0 VGA compatible controller: ATI Technologies Inc RS880 [Radeon HD 4200]
01:05.1 Audio device: ATI Technologies Inc RS880 Audio Device [Radeon HD 4200]
02:00.0 Network controller: RaLink RT2860 Wireless 802.11n PCIe
03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 02)
04:07.0 Multimedia video controller: Conexant Systems, Inc. CX23880/1/2/3 PCI Video and Audio Decoder (rev 05)
04:07.1 Multimedia controller: Conexant Systems, Inc. CX23880/1/2/3 PCI Video and Audio Decoder [Audio Port] (rev 05)
04:07.2 Multimedia controller: Conexant Systems, Inc. CX23880/1/2/3 PCI Video and Audio Decoder [MPEG Port] (rev 05)
04:0e.0 FireWire (IEEE 1394): Texas Instruments TSB43AB23 IEEE-1394a-2000 Controller (PHY/Link)

modprobe of cx:
cx88_blackbird 18631 0
cx2341x 13861 1 cx88_blackbird
cx22702 6748 1
cx88_dvb 27155 0
cx88_vp3054_i2c 2463 1 cx88_dvb
videobuf_dvb 6779 1 cx88_dvb
dvb_core 111007 2 cx88_dvb,videobuf_dvb
cx8802 15729 2 cx88_blackbird,cx88_dvb
cx8800 34890 3 cx88_blackbird
cx88_alsa 10815 2
cx88xx 83667 5 cx88_blackbird,cx88_dvb,cx8802,cx8800,cx88_alsa
v4l2_common 19935 6 cx88_blackbird,cx2341x,wm8775,tuner,cx8800,cx88xx
videodev 43828 8 cx88_blackbird,wm8775,tuner,cx8800,cx88xx,v4l2_common
ir_common 49030 1 cx88xx
snd_pcm 105589 5 snd_pcm_oss,snd_hda_intel,cx88_alsa,snd_hda_codec
tveeprom 13945 1 cx88xx
ir_core 8190 2 cx88xx,ir_common
videobuf_dma_sg 13554 6 cx88_blackbird,cx88_dvb,cx8802,cx8800,cx88_alsa,cx88xx
videobuf_core 20421 6 cx88_blackbird,videobuf_dvb,cx8802,cx8800,cx88xx,videobuf_dma_sg
btcx_risc 4704 4 cx8802,cx8800,cx88_alsa,cx88xx
snd 84412 35 snd_pcm_oss,snd_mixer_oss,snd_seq,snd_seq_device,snd_hda_codec_realtek,snd_hda_intel,cx88_alsa,snd_hda_codec,snd_hwdep,snd_pcm,snd_timer
i2c_algo_bit 6728 3 cx88_vp3054_i2c,cx88xx,radeon

I don’t get any error messages or dmesg on this so nothing there.

I recommend you check your wiring and also your grounding. If it starts ok, and then builds up white noise, it suggests to me a hardware capacitive effect is being built up, causing the noise.