After 1.5 hours, I have booted back into linux and I can immd. see that I don't have to wait for even 45 seconds on pbs to make it produce pops.
I notice this occurring in the mythtv logs pretty often, but its not there for every pop. 2007-01-22 19:16:34.386 WriteAudio: buffer underrun 2007-01-22 19:16:34.536 NVP: prebuffering pause -devsk ----- Original Message ---- From: devsk <[EMAIL PROTECTED]> To: Communications nexus for pvrusb2 driver <[email protected]> Sent: Monday, January 22, 2007 6:12:44 PM Subject: Re: [pvrusb2] audio pops and cracks in the recordings > Anyway, I think you definitely need to run the device under Windows and test > the audio there. ok, I have been watching the pbs channel for more than 45 minutes in windows xp pro and I can't hear even a single pop so far. The channel has played much more intense music compared to the clip I posted earlier. So, it doesn't look like the device problem. I have tried various channels (CMT has lot of guitar and no pops there) and no pops anywhere so far. Where do we go from here? I will stay in windows xp until I hear from you, if you want me to do some troubleshooting in windows. And also to see if with time it heats up or something and starts popping.....:) -devsk ----- Original Message ---- From: Mike Isely <[EMAIL PROTECTED]> To: Communications nexus for pvrusb2 driver <[email protected]> Sent: Sunday, January 21, 2007 11:05:49 PM Subject: Re: [pvrusb2] audio pops and cracks in the recordings On Sun, 21 Jan 2007, devsk wrote: > I haven't tried the device in windows. Do I really have to? Do you > think its a device specific problem? Yes, I think it is very possible. I can imagine that bad a filter cap or some kind of failing transistor might produce this sort of distortion. What I find most remarkable is that the example you sent has the pops happening in sync with the energy spikes in the audio track. It really does sound like what you'd get playing audio through a damaged speaker cone. That to me sounds like a hardware issue. Hardware isn't infallible; I was fooled for 6 weeks straight about a year ago chasing a software ghost that turned out to be defective hardware (scan the mailing list from about Dec 2005 and look for stuff about B&W video if you want to see). The best way to prove (or disprove) this sort of thing is to swap out the software and see if the problem still happens. In other words, run it under Windows and see if the audio is ok or not. > > do you think reducing bass (from default 0 value) will help, maybe? It > sounded exactly like you described. Imagine listening to whole 2 hour > Yanni live with those pops here and there, after a while I got sick of > it, although the music was awesome!. Well it's a nice idea to reduce the bass, except it's entirely possible that the bass control is not implemented in the hardware. The msp3400 chip in the 29xxx devices has a datasheet that allows for tone controls, and in fact the Linux msp3400 driver implements these. For this reason the pvrusb2 driver makes those controls available. However it depends on the exact msp3400 variant being used and I've seen examples where the tone control circuitry just isn't there in the chip. (Not sure off the top of my head about 24xxx devices which use a cx25840 chip for audio.) > > The settings were at their default when the sample was taken: cat'ed > the values I changed, before taking sample, to make sure. I am not > sure how to go about debugging this thing. OK. I think your next best step is to try it under Windows. Some advice (from a hard lesson I just learned today): If you are installing the software under Windows 2000 (as opposed to XP), make sure you have your Direct-X installation up to date. The driver CD from Hauppauge includes this, but if you just download the drivers from the web site and install that way, then you'll miss the undocumented Direct-X requirement. I pulled my hair out for a full day today trying to figure that one out. Anyway, I think you definitely need to run the device under Windows and test the audio there. Sorry :-( -Mike -- | Mike Isely | PGP fingerprint Spammers Die!! | | 03 54 43 4D 75 E5 CC 92 | isely @ pobox (dot) com | 71 16 01 E2 B5 F5 C1 E8 | | _______________________________________________ pvrusb2 mailing list [email protected] http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2 ____________________________________________________________________________________ TV dinner still cooling? Check out "Tonight's Picks" on Yahoo! TV. http://tv.yahoo.com/ _______________________________________________ pvrusb2 mailing list [email protected] http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2 ____________________________________________________________________________________ No need to miss a message. Get email on-the-go with Yahoo! Mail for Mobile. Get started. http://mobile.yahoo.com/mail _______________________________________________ pvrusb2 mailing list [email protected] http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2
