Dolby 5.1

[adm]

Being a bit more critical in what I'm seeing/hearing

There seems to be a lip-sync problem between vision and ACC downmix audio over HDMI and SPDIF that appears uncorrectable on the Miraclebox Twin Premium. There is a PCM delay option in the AV menu with a range -1000 to +1000 but this doesn't appear to make any difference to the mismatch (audio ahead of vision).

What I'm observing is with a TV connected via HDMI and using the TV (non-surround) audio/speakers, and as a second test with SPDIF audio into an AV amplifier.

[birdman]

There seems to be a lip-sync problem between vision and ACC downmix audio over HDMI and SPDIF that appears uncorrectable on the Miraclebox Twin Premium. [...]

What I'm observing is with a TV connected via HDMI and using the TV (non-surround) audio/speakers, and as a second test with SPDIF audio into an AV amplifier.

I'm not aware of having seen this.
There is an AudioSync extension, which might have additional options. (The relevant source files are all named AC3*, but ...).

[adm]

I'm not aware of having seen this.
There is an AudioSync extension, which might have additional options. (The relevant source files are all named AC3*, but ...).

I suspect that the functions of some of the plugins have already been incorporated into the existing VIX image. There is already an inbuilt AC3 and PDM audio delay option but these don't seem to apply to to the digital audio output when viewing UK terrestrial TV. As I can only get downmix 2 channel with my (external) equipment I'm currently using the RCA outputs for audio which appear to have better (but not perfectly synchronised) lip-sync, with my set-up.

I should point out that surround sound isn't new to me. I'm on my second AV amplifier and that was purchased 6 years ago - and before that NICAM stereo on UK broadcasts. Other (4 off) equipment does work as expected with my set-up using SPDIF connections.

I'm beginning to think that with the existing hardware/software (VIX Apollo image 41) the Miraclebox Premium Twin is unsuited to UK terrestrial TV. It does a lot of things very well but is let down by it's audio capability. Perhaps I'm not surprised as its pedigree seems to be from the satellite background.

As I've said before I can adapt the box for satellite usage and this may be the way forward for me. I will try with plugins etc. for a while because watching/recording TV is not a priority for me and I must get on finishing my bathroom and refurbishing the central heating before the weather gets too cold