Hello, since day one with my PI2B I faced the following problem:
Everytime I play a 24p (by 24p I mean 23.976fps) video - e.g. a bluray rip - on my BenQ TH682ST the Beamer looses the connection for a split second resulting in a 3-5s black screen to reconnect to the hdmi signal (beamer sided). This happens a few seconds after the movie starts playing for the first time and two times for the the following 1-2 minutes. After the third “blackout” there is no issues for the rest of the movie at all. When I pause and resume the movie the blackouts reappear (3 times after each pause with comparable timings).
This never happened with 25p, 30p and 60p videos and my Samsung TV doesn’t loose the connection either.
At this point you might think the problem is the BenQ beamer but the strange thing is that I can eliminate the issue by turning the “auto video refresh rate” feature completely off. Everything is running smoothly when refresh rate is locked to 24 Hz in Rasplex. Of course I can manually switch to the appropriate refresh rate every time I start a movie at the cost of comfort but I am not willing to give up on that issue without at least trying. Maybe some has an advice what I can try to fix this issue?
Rasplex and PMS are up2date and I am using a wired connection.
What I tried so far:
- “auto refreshrate feature” to “at start/stop” --> no difference to “always”
- force video transcode @10Mbit
- enable/disable vertical blank sync
- pause movie immediately at start for a minute
- checked cache (seems to work properly; filled up to 100MB)
- multiple hdmi cables short/long with and without timing correction
- local playback from WDTV Live Hub (has a auto refresh rate feature as well) --> no blackouts with the BenQ Beamer!
My thoughts:
I think Rasplex might struggle to find the correct refresh rate and switches between 23.976 and 24p what causes the hdmi connection to reset resulting in the beamer to reinitiate the connection (3-5s blackout is normal for this Beamer when changing source). The Samsung has probably a better handling when the signal changes so there is no interruption noticeable (my theory). That said, setting “auto framerate feature” to “at start/stop” should have fixed the issue in my opinion, but it doesn’t.
My approach (which I can’t realize without help):
I would like to disable 23.976Hz or 24Hz refresh rate completely so it cannot be used by the auto refreshrate feature and see if that makes any difference. Can this be done easily in a config file?
Do you have any other suggestions?
I got same problem with X500… Picture is actually good with OpenPHT, but Pht gives this problem… But OpenPHT messes with audio…
@Alexander Uhl said:
Hello, since day one with my PI2B I faced the following problem:
Everytime I play a 24p (by 24p I mean 23.976fps) video - e.g. a bluray rip - on my BenQ TH682ST the Beamer looses the connection for a split second resulting in a 3-5s black screen to reconnect to the hdmi signal (beamer sided). This happens a few seconds after the movie starts playing for the first time and two times for the the following 1-2 minutes. After the third “blackout” there is no issues for the rest of the movie at all. When I pause and resume the movie the blackouts reappear (3 times after each pause with comparable timings).
This never happened with 25p, 30p and 60p videos and my Samsung TV doesn’t loose the connection either.
Auto ‘refreshrate’ feature attempts to reset the display (your BenQ) refresh rate to match the played media. It’s used to prevent audio resampling and stretching so that the video and audio stays in sync, by playing both at the rates native to the media file. The BenQ probably has a longer reset mechanism when it changes refresh rates than your TV. This is the 3-5s black screen you’re seeing.
In contrast “Sync to display” syncs the played media framerate/audio to the display’s refresh rate instead.
At this point you might think the problem is the BenQ beamer but the strange thing is that I can eliminate the issue by turning the “auto video refresh rate” feature completely off. Everything is running smoothly when refresh rate is locked to 24 Hz in Rasplex.
Yup. Because Rasplex/OpenPHT is not requesting the BenQ change it’s refresh rate to match the media. Rasplex/OpenPHT will use what ever is your display’s highest refresh rate for menus. You’re manually forcing all the refresh rates to 24hz, which means Rasplex/OpenPHT never requests the BenQ change it’s refresh rate.
What I tried so far:
- “auto refreshrate feature” to “at start/stop” → no difference to “always”
“at start/stop” mean’s Rasplex/OpenPHT will request the BenQ change it’s refresh rate at the beginning of playback and when playback ends or “stops”.
- force video transcode @10Mbit
This usually doesn’t affect the Frame rate and thus has no effect on the request display refresh rate.
- enable/disable vertical blank sync
This usually doesn’t affect the Frame rate and thus has no effect on the request display refresh rate.
- pause movie immediately at start for a minute
Not a cache issue. This would only help if it needed to download (cache) more of the stream to avoid transport drops.
- checked cache (seems to work properly; filled up to 100MB)
See above.
- multiple hdmi cables short/long with and without timing correction
Does not affect frame rate or refresh rate.
- local playback from WDTV Live Hub (has a auto refresh rate feature as well) → no blackouts with the BenQ Beamer!
The menu may always be displayed in 24hz so you’d see the a refresh rate change less frequently. You’d have to play 29.97 FPS content or above to see a change
My thoughts:
I think Rasplex might struggle to find the correct refresh rate and switches between 23.976 and 24p what causes the hdmi connection to reset resulting in the beamer to reinitiate the connection (3-5s blackout is normal for this Beamer when changing source). The Samsung has probably a better handling when the signal changes so there is no interruption noticeable (my theory). That said, setting “auto frame rate feature” to “at start/stop” should have fixed the issue in my opinion, but it doesn’t.
The opposite in my opinion. The BenQ is struggling.
My approach (which I can’t realize without help):
I would like to disable 23.976Hz or 24Hz refresh rate completely so it cannot be used by the auto refreshrate feature and see if that makes any difference. Can this be done easily in a config file?
I don’t know if there is a way to set the menu refresh rate to 24hz to minimize the resets without impacting the whole content playback system. But that would be a better solution than preventing all content from running at it’s native frame rate.
@jhalttu said:
I got same problem with X500… Picture is actually good with OpenPHT, but Pht gives this problem… But OpenPHT messes with audio…
Have you taken a look at this document?
https://forums.plex.tv/discussion/181255/rasplex-guide-to-audio-settings-updated
Yes… No help. If soundtrack is AAC, then it always messes audio (track go wrong places…)
I have tried pass trhu no pass thru… 5.1, 7.1, etc speakers (i got Denon X4200W with 7.2 setup)
Do you plug your HDMI cable directly from the rPI to the Denon x4200w HDMI Input? Or do you connect it to another device and then use an SPDIF connection to the Denon receiver?
Like:
rPI > HDMI > TV > SPDIF > Denon
@benjaminwolf said:
@Alexander Uhl said:
What I tried so far:
- “auto refreshrate feature” to “at start/stop” → no difference to “always”
“at start/stop” mean’s Rasplex/OpenPHT will request the BenQ change it’s refresh rate at the beginning of playback and when playback ends or “stops”.
@benjaminwolf said:
@Alexander Uhl said:local playback from WDTV Live Hub (has a auto refresh rate feature as well) → no blackouts with the BenQ Beamer!
The menu may always be displayed in 24hz so you’d see the a refresh rate change less frequently. You’d have to play 29.97 FPS content or above to see a change
at first, thank you for your comments.
What you described isn’t working as expected. I set Rasplex to “at start/stop” (from “always”). As expected, refresh rate changes at playback start and stop, causing the hdmi connection to reset (thats not the problem). But the hdmi connection seems to reset at lets say 50-60s into the movie for the second time and some seconds or minutes later for the third and fourth time. These resets are the real problem because they occur on every movie and I cannot think of a reason why the hdmi connection is reset. There are always (exactly!) three additional resets which i cannot explain (beside the initial reset due to the change for the proper refresh rate). In addition, these three additional resets occur some seconds or minutes after each playback pause (refresh rate doesn’t change while pausing, so it shouldn’t be a necessary to adjust the refresh rate afterwards and the beamer isn’t turning into power saving mode or similar).
The WDTV Live Hub displays the menu at 60 Hz. The BenQ and my TV displayed the incoming refresh rate. Thats why I think this could be a Rasplex problem.
I tried different things like “forced transcode”, multiple hdmi cables etc. to make sure the problem is not related to a cheap hdmi cable, a specific file or the PI2 struggeling to decode the file properly causing some hiccups.
What I currently do to avoid that problem is manually set the refresh rate to 23.976 and disable the “auto refresh rate” feature prior to playback over the BenQ. I never had any hdmi connection reset this way and everything is running smoothly. That said, I cannot think of another reason than Rasplex initiating the hdmi reset even though it is not supposed to do that with “auto refresh rate feature” set to “at start/stop”.
Any further ideas on this topic will be much appreciated!
Hmm, this sounds very similar to what I experienced with OpenELEC/Pi3 and a BenQ projector - if i remember correctly when Omxplayer acceleration was disabled the proper delay took effect and no further reset. I don’t think I ever had more than a couple at beginning of movie - first 20-30seconds for example.
It doesn’t sound like your issue but you could try disabling omxplayer acceleration and also if you use an av receiver maybe turn projector on first, then av receiver, then pi. That order of device switch on seems to give me the best results.
@Griml0ck said:
Hmm, this sounds very similar to what I experienced with OpenELEC/Pi3 and a BenQ projector - if i remember correctly when Omxplayer acceleration was disabled the proper delay took effect and no further reset. I don’t think I ever had more than a couple at beginning of movie - first 20-30seconds for example.
It doesn’t sound like your issue but you could try disabling omxplayer acceleration and also if you use an av receiver maybe turn projector on first, then av receiver, then pi. That order of device switch on seems to give me the best results.
Thank you for the tip! I disabled Omxplayer and it looks good so far. As I an able to reproduce the issue with Omxplayer acceleration enabled and it didn’t occur once during two test runs I think this is the cause of the problem.
