Thanks Kevin. I was hoping it would occur in one or the other and not both.

Found another CD that has signal lock issues with the 950. Smashing Pumpkins Earphoria. The 950 loses lock in between some of the tracks.

Another one: The Cure's Bloodflowers. At least in between tracks 4 and 5.

I seem to either be noticing this more recently, but I hope it's not a case where it's getting worse.

Every type of digital audio signals has a unique pattern (Dolby Digital AC-3, Dolby Digital EX, DTS, DTS-ES Matrix 6.1, DTS-ES Discrete 6.1, DTS 96/24, HDCD, MPEG-1, Layer III, MPEG Multichannel, Linear PCM, and yes even digital silence (all 1's or all 0's).

With this in mind, the DSP is responsible for reporting to the host microcontroller (Toshiba 100-pin part located on the main board) what "pattern" it currently is seeing.

If it sees AC-3 (Dolby Digital), then it tells the host controller, "I have autodetected a Dolby Digital signal, please load the Dolby Digital code (or Dolby Digital EX code or Dolby Digital 2/0 + Pro Logic II code or Dolby Digital + Cirrus Extra Surround code) - depending on what processing mode the listener prefers"...the controller does just this.

So, imagine if you will that a Linear PCM stream contained a small segment of data that "looked" identical to that of AC-3, DTS or some other type of compressed data or digital silence...

The DSP would originally report that it was processing Linear PCM data...but then, all of a sudden, the stream emulates that of a compressed stream...so the DSP reports that the stream type has changed to the host controller and automatically mutes the outputs... the host controller, then starts to load the proper DSP code to decode this new type of stream... but just as it is finished, the DSP then reports to the host... now the stream is Linear PCM again... please load the preferred PCM processing code... this would sound to the listener as a "drop in audio" or a brief muting of sound, when there should not have been one.

The "initial" signal lock time, has more to do with the S/PDIF receiver. The 950 uses the world-standard Cirrus Logic "Crystal-brand" CS8415A, so lock time for almost any bi-phase mark encoded signal (regardless of the physical connection being optical or coaxial) should be around .5 to 2 seconds, depending on the quality of the biphase mark encoded signal being transmitted from the source, and the sampling frequency.

Keep in mind that a S/PDIF receiver only converts biphase mark encoded data to I2S digital audio format, which is fed to the DSP. If the S/PDIF transmitter in the source device (CD player, DVD player, STB, DAT machine, etc.) stops sending a valid biphase mark encoded signal (which can happen during a track change or station change or FF or RW, depending on the manufacturer)

The DSP inside the 950 is a Cirrus Logic "Crystal-brand" CS49326 (www.cirrus.com) which is a dual-engine 24-bit, fixed-point Audio DSP. It is the worlds most commonly used Audio DSP in most of the AVRs and Processors.

Try disabling the "autodetect" feature and select PCM only for these "troublesome" CDs see if an audio dropout still occurs... surely there was some reason why this ability is included in the 950.

The Oracle has spoken...



[This message has been edited by Scott (edited February 05, 2003).]

Hmmmm.... Maybe it's just Kevin's taste in music - none of my CDs exhibt this behavior

I used to know a guy named Mark, who was bi-polar - is this the same thing?


[This message has been edited by soundhound (edited February 04, 2003).]

Whoa. Hello Oracle....I love this place, so many things to think about.

PS. use Toslink currently no dropouts here notated to date.

[This message has been edited by Smart Little Lena (edited February 04, 2003).]

TO- Something to try. I suppose then that when I play a DVD, I have to change the setting, but will be interesting to check.

SLL: I have the problem with Toslink too, even with a different player. My red dot (equivalent) did it as well as this blue dot (equivalent).

Yeah, I was just thinking that as I come across CDs that do this, everyone gets a peak into what I'm listening to...

True, or you could do this -- configure an "extra" input (I'm using AUX2 at the moment) to use the DVD player's digital input. Then you can set it up for CD playback only (stereo or PLII as you prefer, disable autodetect). Set up a macro to change to that input (saves having to cover the front of the remote to switch back to DVD), and you are good to go without messing with the DVD input's settings.

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gonk -- Saloon Links | Pre/Pro Comparison Chart | 950 Review

OK, if I do "dedicate" the digital input, as expected (if you think about it for 2 sec), it does eliminate the 950 losing the lock.

Gonk- I had thought about your way too, but not long enough. I would use the CD input for coax1/PCM say, and then DVD for coax1/auto. But I already have a CD burner hooked up into the CD input. But now that you mentioned it: aux... Cool.

Just curious, but *no one* else out there has this problem? I haven't seen anyone else post about losing the lock *within* a CD, just say switching between cable or DSS boxes an stuff. Even if it is something unique to the player I have, I know there are other people out there with the Pioneer DV-45a/47ai / 950 combo. (My HHB burner also exhibits this, but I believe that it has a substantial % of Pioneer component inside.)

Well, if one has to snoop the data stream to sniff out what sort of data is being transmitted the protocol is pretty poorly thought out. Working with idiotic protocols sucks; If this is really the case I feel for the poor slob that had to work on it - I always walk away from that sort of thing feeling like I should wash my hands or something.