Buzzing noise while Contour Record 6 (Cisco 9865HDC) DVR is on pause

What happens if you connect the DVR direct to the TV via HDMI? Does the buzzing sound come from the TV speakers?  Also, what is your surround sound receiver set to? Dolby?

Thanks for the question.  I appreciate any thoughts.

The TV is not a 5.1 sound system, so plugging the hdmi cable directly to the TV does not reproduce the problem since the audio output there is stereo PCM.  So no buzzing when connected directly to the TV. 

My receiver auto-detects the audio format for whatever the particular media is outputting.  So when the show or media is in Dolby, the receiver outputs as DD; if it is Dolby TrueHD, then the receiver switches to Dolby TrueHD; PCM Stereo comes out as PCM Stereo. Since the audio format of the DVR changes based on what the particular show or channel supports, my receiver can handle this automatically. All my other components work this way and they sound fine.  My previous DVR also did this fine.  Just this new one has the issue.

When the DVR is on pause, my receiver indicates that the audio stream is reverting from from Dolby to PCM. That's when the buzzing sound comes from my speakers. Interestingly, the same thing happens when I'm fast-forwarding (changes from DD to PCM) but I don't get that buzzing noise when fast forwarding.  Only when on pause, and only when on a recorded show.

So let me see if I have this right. DVR > Surround > TV via HDMI. DVR set to Dolby, Surround set to auto-detect. If you pause a recorded show, you get a audio buss from your surround. Does not happening during live TV, or even pausing live TV. Does not happen while watching recorded shows, only when pausing recorded shows. Doesn't occur with other items and happens both HDMI and SPDIF.

1. Anyone know of a manual for this box's software? Need to see the Audio Output options.

2. Does FF and then going back to pause fix the issue?

3. Does it happen with all recorded shows?

4. When it happens does the receiver still detect the sound as what ever it was detecting it as when unpaused?

5. Does it happen on recorded SD shows?

6. Overall it sounds like a software bug with the way the the way DOLBY is being encoded onto the MP4  when saved. Maybe something to do with the real time transcoding.

Also, did this problem just happen? Seem in last week there was a new firmware push.

1. Not sure about that.  I looked for a manual online but haven't found anything. Was really curious to see if anyone else has this problee, but haven't heard anyone complaining.

2. Interestingly, FF and then going back to pause DOES stop the buzzing.

3. This happens with all recorded shows.  It also happens with all on-demand shows like HBO on demand, etc.

4. yes, when I unpause, it correctly goes back to DD and the buzzing stops.  It's only when in pause (reverts to PCM while in pause) that it buzzes.

5. YES.  This does happen on just SD recorded shows.  It also happens if I pause a live show and wait a few minutes and hit play (so I'm watching a recorded stream) then pause again.

6. Yes, it does sound like a software bug.  But I am very surprised that no one else is reporting it. I think I've got a fairly common configuration.

I just got this box installed last Friday. It's been like this since it's installed.

Most of the items addressed in the latest firmware patch have to do with the record system it seems, so its quite possible once your unit updates that problem might be fixed.

There might be a fix though, can you adjust the dynamic range of the audio output?  I think the DVR is defaulting to PCM when no other output is being sent and some setting with PCM on the DVR is causing a problem. If you can just correct the PCM issue, maybe it won't cause the buzzing when it defaults. Could be a work around fix. I just can't give specifics because I have never used that DVR and there doesn't seem to be a manual for it online.

I thank you for your interest and comments.  I have tried changing the dynamic range and other audio settings on the DVR to no avail. So that proposed workaround doesn't work. But I am intrigued by a possible firmware solution. Do you know what the latest available version is?  I know how to get to the diagnostics page on this box, but I don't know what firmware version I should have. 

Thanks again for all the suggestions.  I wish I knew if this was happening to others. Sure seems like a defect.

No I do not. I don't have that type of DVR. Sorry.

But I did post on this thread asking if the OP knew since it seems applied he was aware of the update or knew something about it.

I agree. The bug is reverting to PCM when pausing a recorded or cached program. That "bug" wouldn't normally cause as severe of a symptom unless they had your particular setup and configuration. I think most will just have the DVR connected to a TV so Im not surprised this is the first I have heard of this glitch. So yea, good info.

I have the SAME exact issue. I'm thinking that for some reason they don't mute the audio track when it's paused for some reason. If you notice if you have it at 2x speed you still can here sound from the audio track as it's being sped up. Btw I have mine hooked up via HDMI via my Onkyo TX-NR808.

Well, it's good to know I'm not alone. :) We have the same receiver, so my workaround should work for you too.  Go to the setup menu for the receiver and enter 5. Listening Mode Preset.  Select whatever device you have for the DVR, then for Analog/PCM, select Direct. Save the settings. The thing that threw me at first was that you then have to power off and back on the receiver or these settings don't take effect.

Definitely a bug in the DVR software, but this workaround works for me. Very happy about that as the buzzing is amazingly annoying.

Good luck!