Trouble Playing Dolby Digital Multi Audio

[koberulz]

Put in a commercial just now, intending to watch it. The audio kept cutting out for a second or so, then coming back. Sometimes getting really crackly, then cutting out and coming back fine. Rewinding and playing it back over worked.

So I popped the disc, and put in another and had the same issue. Tried a DVD, it worked fine. Tried a Blu-Ray I'd burned, got the initial problem. Noted that all failures had occurred on Blu-Rays with Dolby Digital Multi audio. Tried a commercial disc with a TrueHD audio track, and it worked fine.

Put the home-burned Blu-Ray in my PS4, it worked fine. Put it back in the Blu-Ray player, still a problem. Switched the HDMI cable from the PS4's input to the Blu-Ray player's input, and it worked fine.

Currently working on the assumption that the HDMI cable is the problem. But, before I go and buy one, thought I'd double-check here and see if there's anything else I may have missed.

EDIT: Scratch that. Was just watching Netflix, via my Smart TV and an optical audio cable out to my sound system. Lost sound for a second once, about half an hour in. With the Blu-Rays, the problem occurred within a couple of minutes, and frequently. I've also been watching streaming video all day through a laptop connected to the TV with an HDMI cable and then the same optical cable out to the sound system, and haven't noticed a problem.

The Netflix show was 5.1, though, and the internet stream would only have been stereo, so it could still possibly be that. But now I have no idea.

[Krispy Kritter]

A cable would be the easiest and cheapest solution. After that, I'd suspect some sort of hardware fault.

Also, verify your audio streams before making any assumptions. Most TV's do not pass through digital surround audio. They will pass surround audio tuned using the TV tuner and TV apps, but any other audio source (ie: any audio input into the TV} gets sampled and output as stereo. Not totally relevant in this case, but knowing the types of audio being used in your experimenting/testing could be helpful.

[koberulz]

Netflix was a Smart TV app, the internet stream through the laptop was, as noted, in stereo anyway, and the BD player is HDMI in to the amp, then HDMI out form the amp to the TV.

Although it turns out my BD player was converting everything to PCM before sending it to the amp anyway, so the audio format isn't the issue.

It can't be the cable, because it occurs through the optical cable from the TV to the amp, the HDMI cable from the BD player to the amp, the HDMI cable from the PS4 to the amp, and the HDMI cable from the Foxtel STU to the amp.

I took it in to the place I bought it from, and they had no idea and suggested, since they were about to close, and the next day was a public holiday and they weren't open so nothing would happen until yesterday anyway, that I take it home and try only having one input plugged in at a time, to see if a cable was causing issues with everything somehow. I tried that, adding cables back step-by-step, eventually getting it back to exactly how it was when the problem occurred, and watched six hours of the BD that had the most problems without a single sound drop-out.

And then, yesterday afternoon, it happened again. Every couple of minutes. Gave up, popped the disc, killed the amp, and watched a DVD through the TV speakers. During that, I decided to move one of the rear speakers back to where it should be, as it'd been in the middle of the floor because it couldn't reach the back of the amp from where it was while keeping the cables out of the way (I have the amp outside the TV cabinet, for easy access, whereas it's normally inside), and figured having cables running along the floor was a better option than having a speaker sit in the middle of the room with cables running at chest height. It's connected via two speaker cables twisted together, and taped with electrical tape, because that's the only way I could get it long enough. While pulling it down from where it was, I noticed that the tape had come loose, and the positive and negative speaker cables were touching.

I have no idea if that could cause the fault--it would explain the perfect stereo but constantly-muting surround sound--or if it was even the case before I'd moved the speaker and its cables, though. But I re-taped the speaker cables, turned the amp back on, and finished watching the DVD I was watching with no problem (although it was only stereo), and then a further hour and a half or so of the BD. Also no problem.