Surround sound problems with new BT 15.11 software
scott
Member, Super User Posts: 2,134 ✭✭✭
Firstly I would like to give a big thankyou for getting the new IP recording software release out it is very welcome.
Unfortunately this has highlighted even more the surround sound issue for me. All my tests have been done over optical (if anyone could repeat the tests over HDMI it would be very much appreciated just to see if there is any difference).
Here are my findings so far with a small amount of testing.
BT TV on Demand
HD 5.1 movies appear to switch correctly
SD and HD none multi surround movies appear to play in stereo from the start needing the menu/surround workaround applying to get surround sound as is the same for the tv box sets and kids on demand.
IP Channels
HD sports channels i.e. BT Sports 1,2 and ESPN (I have hidden the SD versions so haven't tested them) appear to a switch to surround sound correctly
All other channels start in stereo and require the AD button on/off workaround to switch to surround sound.
IP Channel Recordings
Here lies the real problem for me now. Any IP channel recordings (not tested sports channels yet) start in stereo and require the AD on/off button workaround to switch to surround sound BUT as soon as you apply a fast forward or rewind when it starts to play again it has switched back to the stereo feed which is a much higher volume. I hope you can appreciate how annoying this gets that everytime you fast forward/rewind a recorded IP channel to sound switches and starts playing at a higher volume until the workaround is applied (everytime).
Obviously the freeview channels all appear to switch and work fine.
I am sure there is more to find but I just felt it worthwhile getting the issue highlighted AGAIN now the recording ability increases the visibility of this bug.
Unfortunately this has highlighted even more the surround sound issue for me. All my tests have been done over optical (if anyone could repeat the tests over HDMI it would be very much appreciated just to see if there is any difference).
Here are my findings so far with a small amount of testing.
BT TV on Demand
HD 5.1 movies appear to switch correctly
SD and HD none multi surround movies appear to play in stereo from the start needing the menu/surround workaround applying to get surround sound as is the same for the tv box sets and kids on demand.
IP Channels
HD sports channels i.e. BT Sports 1,2 and ESPN (I have hidden the SD versions so haven't tested them) appear to a switch to surround sound correctly
All other channels start in stereo and require the AD button on/off workaround to switch to surround sound.
IP Channel Recordings
Here lies the real problem for me now. Any IP channel recordings (not tested sports channels yet) start in stereo and require the AD on/off button workaround to switch to surround sound BUT as soon as you apply a fast forward or rewind when it starts to play again it has switched back to the stereo feed which is a much higher volume. I hope you can appreciate how annoying this gets that everytime you fast forward/rewind a recorded IP channel to sound switches and starts playing at a higher volume until the workaround is applied (everytime).
Obviously the freeview channels all appear to switch and work fine.
I am sure there is more to find but I just felt it worthwhile getting the issue highlighted AGAIN now the recording ability increases the visibility of this bug.
0
Comments
I'm not getting my head round this at all :-(
When surround sound is being sent, you get surround sound. But when it's not being sent, you get stereo. Yes?
But for you this is unsatisfactory, and you want surround all the time.
So you press a button on your YV remote whose sole jobs in life are to switch AD on and off, and alternatively to toggle upper/lower case in Search (unless the BT remote is different in this respect from my retail one, which is possible I suppose), and you then get surround. For a bit, anyway, but only until you disturb it in one of several ways.
As you are using optical out, I presume you are feeding the signal to an AV amp? And the AV amp can synthesize 'surround', which is the sound you get when you press the AD button to get surround?
In which case, it seems to me that it's entirely a happy accident that choosing AD kicks your amp into this mode, and perhaps not surprising that it kicks itself out again under the various circumstances you describe.
But if you want the amp to be in a "Real Surround if it's available, else Synthesised Surround" mode, and stay in that mode, then that's something that surely you need to configure on the amp, or else enter a dialogue with the makers of the amp if this can't be done.
Certainly, it's how my Sony 5.1 amp can be set to operate, though this is in a different setup from the one my YouView box is in, so I'm not running these together.
Or is this perhaps analogous to the 12:9 in 16:9 picture thing, whereby the 'stereo' you get is L and R on the 5.1 with the other 4 channels silent? I don't think it can be, since if the amp was fooled by this, it would still be showing 'Surround', not 'Stereo'.
But not knowing what the amp is, nor how it is configured, nor exactly what your expectations of the YouView box are here, I remain puzzled.
Can you enlarge on the issues at all?
Although one supposition I have regarding the AD button.
Technically it's not really just for audio description as it just mixes audio from two audio channels together. If the channel that usually contains AD contains audio but no AD, then it will be a mix of two identical channels - hence the change in volume, and switch in amplifier mode..
When I set 'surround' in my settings I should get the Dolby Digital feed (as I do on all the freeview channels) at all times, I should not have to use a workaround (the AD button press is just the easiest way to get it to do it, nothing to do with the buttons actual function).
This fault has been noted multiple times across these forums and is not new. Do a search for Dolby Digital sound faults and you will find it. Obviously I have raised it again because of the IP recording issue highlighting it even more. It is not an amp problem as it can be fixed by going in and out of surround mode in the settings.
But perhaps we now finally have one.
You are saying that you are using Optical Out, set to send 5.1
And when there is 5.1 present, it sends 5.1
But when there isn't, you are expecting to get Dolby Surround 2.0, and yet you often/mostly get Stereo 2.0.
But by a couple of means, you can kick the YouView box into giving you Dolby Surround 2.0, after which your amps sees this. Until certain circumstances, enumerated above, cause the YouView box to go back to giving you plain old stereo.
And your AV amp is merely the passive recipient of whatever is being sent, and it in no way implicated in the actual issue here.
So the questions are:-
(i) Where is the Dolby Surround 2.0 coming from?
(a) Is it being transmitted, but incorrectly being downmixed to plain ordinary stereo by the YouView box under certain circumstances?
or
(b) is it being synthesised by the YouView box, which incorrectly stops synthesising it under certain circumstances?
If (a) applies, then
(c) is Dolby Surround always transmitted? Are there no programmes being sent in plain ordinary stereo, ever?
(ii) Why does the AD workaround work? Is this another bug, and two wrongs do make a right, or what?
Perhaps someone from the recently rather quiet YouView team can shed some light by replying to these questions, which do not carry the implication that YouView should fix the problem, if problem there be, on any given timescale or indeed on any timescale at all?
But by knowing more about the bug, if bug there indeed is, it may be that we can determine the most effective workaround possible in the current circumstances.
[Edit: I note that my paper 1.0 YouView Guide does not mention Dolby until page 26, but the one on the web has been modified to refer to the Dolby licencing on page 1, though perhaps rather naughtily is still flagged 1.0, even though its page 30 is a new blank page and there are other minor changes....]
All the main HD channels are broadcast with Dolby 2.0.
And if you're very lucky sometimes it is proper Dolby 5.1.
All the players except iPlayer produce Dolby 2.0.
The normal freeview channels seem to give Stereo only playback (workarounds don't switch so guessing there are no Dolby 2.0 stereo tracks broadcast). The freeview HD channels work flawlessly with Dolby 2.0 stereo broadcast straight away (and 5.1 on the rare occasions a program has it) without any wotkaround. The catch-up (I tried Dave and 4od) normal stereo while the adverts are on (workaround doesn't switch) then normal stereo when the program starts BUT the workaround (settings - stereo then back to surround) and bingo Dolby 2.0 stereo. The amp flicks sound during every swap in advert/programme as if they are looking for a Dolby signal but never actually manages to switch unless I do the force swap as above.
This is 10 times worse for ip and on demand (work exactly like the catch up issue) on BT boxes. Its like the box doesn't pick up the Dolby signal even though the surround setting is on and the signal is there. Unless the signal is being broadcast wrongly because it seems to work correctly on the three HD sports IP channels on BT...
This also happens occasionally on BBC HD. Most of us are cursed with an amp that can't do anything with this except play in stereo or, via analogue, DPL.
Your amplifier seems a bit more carefree with 2.0 flagged as 5.1 and allows you, through force, to convert back to 2.0 and then add the dpl filter.
After switching to sound over HDMI (which I would guess most people are using) I find that the force switch doesn't work and so therefore sound over HDMI never picks up the Dolby 2.0 Stereo feed from any of the channels.
Why is this a problem? Well because anyone like me that uses a surround 5.1 system through an amp will use the Dolby 2.0 surround feed (better quality on its own over standard stereo) and use the dolby prologic 2 decoder to produce a reasonable 5.1 sound from the speakers (not ideal but much better than trying to listen to a basic stereo signal pushed out to 5 speakers - something I have been doing from my sky box for years).
I further tested this by going straight to my TV with an optical feed (therefore bypassing the amp altogether) and tried the workaround on a catch up program. Although the TV cannot tell me what type of signal it is getting you can hear a much lower volume when you do the force workaround.
So that begs the question, why a lower volume, what is the box doing differently?
My guess is that it is picking up the proper Dolby 2.0 stereo track and playing it back and this comes out at a lower volume.
This is obviously made much worse for people on BTTV because this is apparent in most IP channels and most on Demand channels also.
Just as an extra answer to al above, the amp identifies the dolby 2.0 stereo track as that (a dolby 2.0 stereo track not a 5.1 track) so the YV box isn't flagging it as 5.1 it is purely sending a Dolby 2.0 soundtrack rather than a stereo soundtrack.
(And Ch4 seem to have given up using the [SS] labelling.)
Can't anyone with a surround sound setup notice the volume difference between bbc1 and bbc1 HD channel
Phil
Thanks,
Phil
Only joking
Phil
I've chased this up, I'm just awaiting a response. Let me get back to you on this one.
There has not been any new concrete information I can provide you with just yet. I do have this thread pinned and I am looking forward to the day I can tell you this has been fixed.
Thanks for your patience.