Thanks for your response Kimi.
Although that behaviour may be best for Europe, in the UK it means many people are burning discs with no sound because the 'Audio Description' stream is, on many shows, present but empty. i.e. Even programmes that do not carry Audio Description still have the stream, but with nothing in it.
It is true that broadcasters' output, here in the UK, still momentarily lose audio stream and AFD (Aspect Format Descriptor) mometarily in between junctions and programme starts, implying that if a stream is not needed for the next programme, it shall not be broadcast. In practice however, this never seems to be the case.
Also - the primary audio stream does not have its language defined here in the UK. The thinking seems to be "well, it would be in English, wouldn't it, being as we're transmitting from the UK?" Only the AD audio stream has its language defined - hence why the REAL audio track shows 'English???' in the DVD Wizard and only shows 'English' on the AD track.
This is almost certainly due to sloppy implementation of the DVB-T (and -S even) standards by UK broadcasters, but this does mean that many UK users end up with a disc that not only does not have the best *quality* audio stream by default, but has a *totally silent* audio stream by default!!! And therein lies the problem which really should be addressed for UK users. Unfortunately, UK broadcasters are not likely to change the way they do things because they have a history of messing up every technical implementation relating to TV ever devised that is data related. PDC (our version of what you would call VPS) was never properly implemented here - it appeared to be, but it was hardly ever synced up to the transmission tapes, only to the scheduled times, meaning it didn't actually provide the intended benefit. Similarly, problems are already being witnessed on the so called 'series link' of Freeview Playback, the general concencus of which will be that the broadcasters here in the UK will never bother to transmit codes to instruct receivers to adjust their recording times, because they're too busy switching feeds in their transmission centre prior to vision mixing, directing and sending to the transmission area than they are keying in instructions into a computer to transmit to the playout server in the transmission centre!!! (phew!)
What you have to understand is that in the UK, TV stations' transmission, scheduling and production areas are very often run with very wide contractual divides between them, meaning that there would be a financial penalty to one party if the other had to supply data over and above their usual contractual requirements when programmes run to time. For instance, the company that provides the EPG data will have a contract with the broadcasters, and the company that transmits the programmes will have a contract with the broadcaster, and getting the two parties to key in and send data over and above their contractual obligations will not be a top priority. It will very often simply not happen at all, to keep financial claims to a minimum for extra work.
You may be unaware of this, but as of around 2 years ago, the BBC's own transmission centre was sold off and is now a private company. That company now has a contract WITH the BBC to 'provide' transmission services. That means if a studio at BBC Television Centre needs to instruct the company that provides the transmission facilities that their programme is going to start 5 minutes late, there will be so many hoops to jump through administratively just to get the transmission time itself altered, that there will be no time and it will be considered too much cost to have somebody else adjusting the EPG and Now/Next data to follow the new transmission time.
Even the other broadcasters tend to run their production and transmission teams as separate businesses who 'buy in' each others' services - nothing is considered 'in house' anymore, and through all of this there will be no financial incentive to hire people just to track changing transmission times (apart from commercial people logging how many advertising minutes may be lost or gained - who will not have the equipment, knowledge, inclination or access rights to key in EPG revisions).
The same will go for audio stream programming. Many of these parameters are programmed into the playout servers en-bloc, meaning that many programmes that were DUE to have Audio Description have the stream 'booked' for transmission even though the audio content may not be delivered on time and inserted into the programme (ingested).
Similarly, some programmes may have been believed NOT to have a secondary audio stream required, or the secondary stream may not have been paid for, and for one of these reasons not set up, but an Audio Description stream added to the programme later, but to keep the cost down of reprogramming the server, not transmitted.
Change the 'Create MPEG File' audio stream dropdown from 64kbit/s to the higher number (192 or 256)
and still it has to be dragged from 'position 2' to 'position 1'.
. We are always open to customer proposals as long as they make sense, don't spoil the concept of the product and are technically and commercially realistic...