Playback juddery

peter

Please send it to support@stagetraxx.com.

And before you do that, please try to increase the audio buffer size in Playback Settings. Maybe this will help

SteveCherelle

Hi. I did that. Just tried again on them all. It’s very odd. Same data base plays fine on any iOS but 16.1.

I have 4 machines now all doing the same issue but not when it’s on the pre iOS 16.

How do I send you a video?

peter

Just email it if it is small (below 20mb). If it is too large, you will need to upload it to a file hoster and send me the share link.

peter

I've tried to reproduce this on both iPhone and iPad running with iOS 16 and I do not see this issue.

Is anyone else experiencing these kind of problems?

MasterAnt

I can confirm this!

Just tested this using three devices:

iPad Pro 2021 iPadOS 16.1
iPhone 14 PRO iOS 16.1
iPad Air 2 i?OS 15.7 (my live gig iPad)

I only tested one song. Any pitch or speed change using 1. or 2. produces wobbly sound, especially audible on bass guitar which is now no longer smooth on long notes.

I have an iPhone 8, but haven't upgraded it to 16.1 yet. Am reluctant to do this for testing, as this is my primary backup player at gigs.

I'll fiddle around more and see if I can come up with anything.

SteveCherelle

MasterAnt
Thanks.
Me and Peter are trying to work it out and so this confirms it’s a glitch somewhere. Best not to update anything for now.
I can’t roll back to 15.

Let’s see what Peter thinks.

MasterAnt

Testing observations so far:

No difference made using any of the four buffer sizes.
Nothing else is set on the track: no eq, fades, volume changes.
Source file is mp3. All my files are compressed the same:
Size: 4493692 bytes
Header found at: 6563 bytes
Length: 186 seconds
MPEG 1.0 layer 3
192kbit, 7167 frames
44100Hz Joint Stereo
CRCs: No
Copyrighted: No
Original: No
Emphasis: None
Not running any master EQ, except for a +6dB volume gain.
Occurs on both bluetooth audio and internal speaker
Occurs in all players: song, edit audio regions, playback & trim
Occurs on all songs I've tested. Less audible on some.
The wobbliness sounds similar to WinAmp + XFX's pitch shifter from the early 2000s, ie. a very early algorithm which had echo artifacts, etc.

Seems like an issue between the algorithm, iOS 16, and the CPU architecture

SteveCherelle

MasterAnt
Thanks for the further testing.
Your description is spot on and so thank you.
I have a back up old iPad for now.
Will leave the new one until we find a solution. It’s a strange one eh.

peter

OK, now that I know what to look for I can hear a difference in the bass between iOS16 and prior versions. It seems that Apple has changed the algorithm in the audio unit that Stage Traxx uses to change speed and pitch. And this change is not for the better. I have compared the sound of iOS pre 16 and macOS Monterey and they both sound the same. Not sure about macOS Ventura as I have not yet upgraded.

Unfortunately there is nothing I can change in the way this audio unit works. I will open a bug ticket with Apple but that can take a lot of time if they react at all. Replacing the audio unit with a custom built is no really an option as I have not the necessary math knowledge and most developers use the stock audio units.

So bottom line: we will be stuck with this until Apple reacts to the bug report.

SteveCherelle

Hi Peter.

Thanks for that reply.
It makes my new machines obsolete and apple may never change it. It’s a pain eh but not your fault. Hopefully the ticket may help.

Perhaps advice users to not do the updates. If ya use those features then back track singers will be stuffed at the gig after they update. I was.

I will awaits any updates. Thanks for always being on hand for advice Peter.

Steve

peter

I found a mention about something similar on the Apple developer forum. Seems like the algorithms Apple uses are hidden from direct access but there is a trick to force the use of a specific algorithm. Through trial and error I found the algorithm that was used in iOS prior to 16 (at least seems like it to my ear). And this dirty hack seems to work (at the moment at least). This hack will be released in version 3.6.3.

SteveCherelle

peter
Legend. Glad it’s raised and can help fellow acts now Peter.

MasterAnt

@peter Nice work finding a hack!! Nothing's more frustrating than being at the mercy of these big corporates.

MasterAnt

Just wanted to acknowledge @peter and @apple that this algorithm is famazing!!! I've never used live speed changes until very recently in ST3—have always remixed my tracks in Logic for different tempos. I still don't use live pitch changes, but I know that I could if necessary.

peter

Version 3.6.3 is now released. Could you check if this issue is fixed for you?

SteveCherelle

Hi. Yes it’s fixed. Have played the affected trax on my phone and they sound fine now. Will try on iPad later when I am home but seems to have resolved it.
Thank you Peter.

MasterAnt

Seems to be working my side as well. Have tested on same three devices and all are sounding correct. Thanks @peter !!

Hatfield413

Thank you all for this! Had the same issue…found an external workaround but appreciate everyone’s diligence and persistence! Thanks Peter!