BT Pro Box Frame Rate Match Bug - Always 60hz when frame rate matching is on.

[expectingtofly]

There is a repeatable bug on the BT Pro Box,   HDMI Frame rate matching causes all freeview to be output in 60hz instead of 50hz

How to replicate the bug :

With HDMI Frame rate matching set to off 

1.  Tune to any channel on Freeview.  The picture is output at 50hz correctly,  matching the broadcast refresh rate

2. Set HDMI Frame Rate matching to on.

3. Return to the picture and it remains at 50hz

4. Put the box into standby

5. Take the box out of standby, the freeeview picture is then output  incorrectly at 60hz.   The picture then remains at 60hz unless you switch HDMI frame rate matching off.

A 50hz picture output at 60hz is really quite an unpleasant experience at best, on most televisions,  and disconcerting on all televisions.

Is this bug known about?

I suggest keeping frame rate matching off until this is fixed. 

However, although I haven't explicitly checked, I have a feeling there is another circumstance with frame rate matching off that can cause the box to inexplicably switch to 60hz.  As I've noticed the stutter on a number of occasions, but not in a way that's repeatable like the above example.

I did a search and notice something similar has been reported on the youview forum, but to no response here (post 5) : https://community.youview.com/youview/discussion/7606943/bt-tv-box-pro-software-update-4-0-216-0-5-2... 

[NeilO]

Hi @expectingtofly welcome to the community and thanks for highlighting this, I'm sorry to see you're experiencing problems with your BT TV Pro box.

I've highlighted your post to our BT TV team, they'll try to replicate the bug and will raise a ticket to get this investigated further.

Thanks

Neil

[MC22]

I hadn’t really noticed this issue until I read you post however, you are of course quite correct, my Pro Box exhibits the same behaviour.  It’s clearly demonstrated when tuning to Sky News HD on 385 when the box has just come out of standby, the news ticker is quite choppy and my TV is indeed reporting a 60hz signal.

I’ve followed your advice and turned off HDMI Frame Rate Matching. 

[Brucemeister5]

I can confirm that the issue identified by the OP exhibits itself on our Pro tv box too.

[expectingtofly]

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@MC22wrote:

I hadn’t really noticed this issue until I read you post however, you are of course quite correct, my Pro Box exhibits the same behaviour.  It’s clearly demonstrated when tuning to Sky News HD on 385 when the box has just come out of standby, the news ticker is quite choppy and my TV is indeed reporting a 60hz signal.

I’ve followed your advice and turned off HDMI Frame Rate Matching. 

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Unfortunately, I fear the bug is worse than just affecting HDMI frame rate matching setting.     I've noticed even with HDMI Frame rate matching off, the picture is in 50hz, but there is something slightly wrong with the cadence, plus there are intermittent dropped frames.  (It's most notable when watching sports)  I've been trying to put my finger on what it is.    I really believe that what this box is doing is natively outputting standard 50hz content as 60hz then converting back to 50hz! 

I know that sounds weird, and I obviously can't prove it,  but I think turning on the HDMI Frame rate matching is giving  us that clue, by removing the veneer of it's 50hz back conversion.    I really hope that isn't the case, and I'm mistaken,  but I'm really becoming very sure of it.

Hopefully as the actual 60hz output of 50hz bug is easily reproducible the whole problem will be addressed.

[expectingtofly]

Hi @NeilO  

Please can you confirm that this incorrect frame rate bug has been acknowledged and a fix is coming?

[expectingtofly]

This bug is still present in the latest firmware.  @NeilO please can you confirm that this bug has been acknowledged and will be addressed.  Many thanks.

[DanielS]

Hi @expectingtofly,

Thanks for posting up today.

I am sorry that this appears to be ongoing. Originally, when Neil reported this, our BT TV team opened a bug ticket to investigate. I've reached out to them to get an update for you.

Thanks
DanielS

[expectingtofly]

For the record, this appears to now be "fixed".    Although there has been no communication on acknowledging the bug or stating that there was a fix.

With HDMI Frame Rate Matching set to on, all content is output at 50hz, apart from the Amazon Prime app, which seems to be the only app that honours the match frame rate setting.   (Incidentally, the Netflix app is back to outputting in 50hz, which as most of their content is 24hz, makes the output very stuttery, ironically)

[Brucemeister5]

Whatever may have happened appears to have been undone again on my box. When I bring it out of standby I need to turn the frame rate matching off and on again to restore it to 50 hz.