Song with Autoplay on | Client lyrics quickly scroll back to top at end of song

AnthonyB

Stage Traxx Version/Build: ST 4.0.11
Device & OS Version: Host: iPad 9th Gen, iOS 26.4.2, Client: iPad 9th Gen, iOS 26.4.2, iPad Pro iOS 26, iPad 5th Gen iOS 16.

Issue Description:
Scenario:

You have Network Session with Client/s connected to Host
You have a Playlist with a song set to Autoplay into next song on playlist
You have Stage Traxx set to load next song in Playlist at completion of previous, or, you are also Autoplaying into the next song in the Playlist
(may or may not be pertinent as didn't have time to validate) You have timestamped lyric sheets

On the Client devices only (i.e. Host does not display this behaviour), when they get to the end of the song that Autoplay is enabled on, before loading the next song lyric page, the current lyric sheet quickly scrolls back to the top. This causes a visual distraction and (fractionally) delays loading the next song's lyric sheet which is not ideal when you are Autoplaying through songs with tight turnarounds.

When I first observed this issue a week ago, I thought it was because I had just setup audio regions on a bunch of songs, so that was the first things I tested disabling. This had no impact on the issue.
The next thing I focused on was Autoplay as we had been doing a test run of song transitions in a new set list for an upcoming gig and I had setup all the Autoplays for the first time to test. It turns out Autoplay was the key attribute as when I tested songs that we 'manually' started, the lyric page doesn't scroll to top on client devices.
I haven't run a set list with Autoplays enabled on songs for many months, possibly since late last year, so this regression could have snuck in at any time in the last 6 months. I didn't see it in early 4.0.x versions in case that is any help in tracking down when something changed to have introduced this.

Steps to Reproduce:

Set up Network Session with Client and Host device
Create a Playlist with 2 songs and set song 1 to Autoplay into song 2.
Ensure all songs have lyrics (mine are all timestamped so I'm not sure if same behaviour occurs with non-timestamped)
Play song 1 (you can scroll to near end of song - no need to play through entire song) then observe the behaviour of the lyrics pane at the end of the song as ST loads the next song.

If you then disable the Autoplay on song 1 and repeat the test you should observe that the lyric page gets to end and when next song loads, the lyrics cut straight over to the next song without quickly scrolling back to the top.

Expected Behaviour: At end of song, Next song lyrics should load.
Actual Behaviour: At end of song, lyrics page quickly scrolls back to top of page and then next song lyrics load

peter

This is an issue with message timing. The song position updates are received in parallel to the song change messages and processed faster. So the client gets the new position update at the same time it receives the new song update but it takes longer to process the new song update. No idea how to work around that without delaying the song position updates (which would make the clients lag behind the host).

I think this is a minor issue, that can be ignored.

AnthonyB

peter I think this is a minor issue, that can be ignored.

My band mates who are using the clients respectfully disagree that it is a minor issue 🙂 It was a big deal to the vocalists who play an instrument. They found it incredibly distracting in the few seconds window between the end of one song and start on the next, when needing to react quickly to what song, what key, capo on/off, etc.

It isn't just the the time for the page to jump back to the top and then change, is a bit like when you get a bright flash and it takes an extra second or two for your brain to get past the moment of discombobulation, refocus, and move on to the next task. So I really hope this behaviour can be looked at and not ignored.

I agree that delaying song position updates so that clients lyric scrolling would lag further behind the host would not be ideal.

Would it be possible to flag the last timestamp in a lyric sheet so that ST knows that once it has processed that event that there cannot be any further position updates received. Then as we get near the end of the song, and have processed the final position event, song change events could be temporarily elevated to be processed at a high priority?

Out of curiosity, why is it the presence of the Autoplay 'flag' on a song (to Autoplay into the next song) that causes the song lyric to scroll back to top before song change, while songs that do not have this flag do not display the behaviour?

peter

With autoplay playback keeps running, so the time updates from the host look something like this:

3:59, 4:00, 4:01, 4:02, 0:00 (here autoplay transition to the next song kicks in), 0:01, ...

As playback does not stop and the client receives the new song info at the same time it receives the 0:00 timestamp, it updates the scroll position to 0:00 while the song change is processed. Song change and time updates are independent messages. And the client can not know that the new 0:00 is not a seek or region change operation.

Btw, I can not reproduce the issue with the steps you provided. Or it happens so fast that I don't see it.

AnthonyB

I've just taken a video (link below) - device on the left is the Host, device on the right is the Client.

Video link - https://1drv.ms/v/c/5b4e2bb68d10f016/IQBeQQ3FoU8cRLmivv8nBz-MAVK8dZXxRm3jZm6bCueLIPo?e=QZsGxd

This isn't a "it's not working 'right' and should be fixed just because" type situation, it is really quite obvious and distracting.

It's a 100% repro for me and occurs on multiple client devices so not tied to older devices or older iOS versions.

I thought I'd ruled out Audio Regions also being an element, but maybe just the fact that I have audio regions setup on the songs on the Host means that irrespective of the Top Panel Display setting on the client (show Audio Regions vs Waveform vs None) that it is sending region info the the Clients and that is a contributing factor?

Let me know if there is anything else you would like me to validate/try and if there's any benefit in me sending over a few of my songs (tracks + lyrics).

peter

OK, I will take a look at it.

peter

I think there might be a lightweight solution to prevent this from happening. I will add that to udpate 4.0.12.

AnthonyB

peter Thank you so much for that @peter !

peter

Should be fixed in version 4.0.12.

AnthonyB

Just tested 4.0.12 - confirmed fixed.

Thank you Peter!