[mythtv-users] Re: Help me find a winner...stinking Kt133

[Pierre-Olivier Bouchard]

My CMI8738 is working fine in ful-duplex with ALSA-0.9.x, I didn't have 
to do anything special IIRC. It's an old (I found it in a Celeron 300A 
system!) PCI AOpen card, not onboard, though.

Pete

Joe V wrote:

>I have a KT133-based board for my MythTV PC (which is
>temporary, I just built it out of stuff I had around
>the apartment).  My CMI8738 on-board sound doesn't do
>full-duplex very well either (with ALSA, I don't think
>I tried OSS).
>
>With ALSA, doing full duplex, the regardless of what I
>set the mixer settings to, the sound would always be
>very low, and turning up the speakers would emit a
>loud hiss.
>
>>From what I recall on the ALSA mailing list, this is a
>known issue with the CMI8738 driver.
>
>My solution was to get another sound card.  I bought a
>Soundblaster 16 PCI (based on the Ensoniq 1371 chip,
>although it's identified as a Creative 5880), and it
>seems to be working well (bought it because it was
>cheap, $30).  The sound is a little strange (almost a
>bit "bassey", with some slur to it), but I'm not sure
>if that's the sound card, or the the incoming video
>(could also be my mixer settings).  This is using
>full-duplex with ALSA, perhaps if I dedicate one card
>to the capture input, and another card to the output,
>the problem might go away.
>
>But, like I said, I haven't had much luck with the
>CMI8738 sound in full-duplex.
>
>-- Joe
>
>--- Edmund Wong <ed at guyline.com.hk> wrote:
>  
>
>>>>The onboard sound might not be the greatest,
>>>>        
>>>>
>>however. It's an AC97 codec 
>>    
>>
>>>>based around the Realtek 9738 chip. Not sure how
>>>>        
>>>>
>>good the line-in quality 
>>    
>>
>>>>is on it. Anybody want to chime in here? 
>>>>        
>>>>
>>Wait, Realtek? I typed that? I must be on crack or
>>something. I meant
>>C-Media.
>>
>>    
>>
>>>The on-board sound is simplex, locked at 48kHz,
>>>      
>>>
>>distorts if you have 
>>    
>>
>>>the volume at > 95%, and too quiet to drive
>>>      
>>>
>>speakers directly. But 
>>    
>>
>>>other than that, it plays sound great! :-) No
>>>      
>>>
>>probs with the quality. 
>>    
>>
>>>I bought a second sound card to handle line-in,
>>>      
>>>
>>and use the on-board 
>>    
>>
>>>for line out. In a stroke of bad luck, the 5.1
>>>      
>>>
>>CMI-based soundcard I 
>>    
>>
>>>bought uses the line-in control for recording
>>>      
>>>
>>volume, so I can't just 
>>    
>>
>>>that sound card for mythtv :-( 
>>>      
>>>
>>If it's locked at 48khz, it's fine for playing
>>MythTV recordings but
>>would potentially cause problems with some of the
>>other modules. Any
>>comments on the quality of the line-in? I'm planning
>>a MythTV box around
>>a similar board and I would flip the functions of
>>the two if it came
>>down to it, personally. Unless, of course, if the
>>onboard sound can be
>>wrangled into supporting other sampling rates.
>>
>>Also, has anybody run the onboard sound in
>>full-duplex?
>>
>>- ED.
>>    
>>