Support

Installing, activating, and what to do when something misbehaves. If none of this covers it, email me.

Installing

One download, free or full - a licence key unlocks the rest in place. The installers are not code-signed, so both operating systems warn you. Here is how to get past it; nothing is disabled permanently.

Updating is the same: run the new installer over the top. Your licence, recents and settings are kept. macOS may re-ask the permissions after an update - unsigned builds count as new apps to it.

macOS

  1. Double-click the .pkg. macOS says it can't be opened - click Done, not “Move to Bin”.
  2. Open System Settings → Privacy & Security, scroll down, and click “Open Anyway”.
  3. A second dialog asks again - “Open Anyway” there too, then confirm with your password or Touch ID.
  4. The installer opens. Follow the steps.
macOS warning: the Stream AB installer was not opened
Step 1. Click Done.
macOS: the Open Anyway button in Privacy & Security
Step 2. Privacy & Security.
macOS asking again: Open Stream AB v1.2.0.pkg?
Step 3. Don't take “Move to Bin”.

Windows

  1. Double-click the .exe. A blue “Windows protected your PC” screen appears.
  2. Click “More info”, then “Run anyway”.
  3. Follow the steps.

If Defender removes the file instead of warning: Windows Security → Virus & threat protection → Manage settings → turn off Real-time protection, install, turn it back on.

Activating your licence

  1. Open the plugin on a track and click the spanner in the top corner.
  2. Paste your licence key in and hit Activate.
Opening the spanner, entering a licence key and activating
Spanner, key, Activate.

A licence covers 2 machines; hit Deactivate on one you no longer use to free the slot. Activation needs the internet once - after that the plugin works offline.

The macOS permissions

Two prompts, once each, full version only. Windows asks for nothing.

Neither affects A/B switching or the gain trim - denying them costs you the track display or the reference’s meters, nothing else.

1. Controlling Spotify and Music

macOS asks whether an app may control Spotify, and again for Music. Allow both - that is what shows the track name, artwork and scrub bar. In Ableton, Logic and Reaper the DAW asks in its own name; Cubase and FL Studio can’t ask, so a small bundled helper asks instead. Same permission either way.

Dismissed one? Re-enable it at System Settings → Privacy & Security → Automation, under your DAW or “Stream AB Helper”.

macOS: Ableton Live wants access to control Spotify
Some DAWs ask in their own name…
macOS: Stream AB Helper wants access to control Spotify
…for the rest, the helper asks.

2. Screen Recording, for the meters

Measuring the reference means capturing system audio, and macOS keeps system-audio capture behind the Screen Recording permission - there is no audio-only permission to ask for instead. Nothing is recorded and no screen is read. The helper takes audio only and produces numbers; nothing is stored or sent anywhere.

The prompt comes from Stream AB Audio Helper, the first time you switch to B. Needs macOS 13 or later.

macOS: Stream AB Audio Helper would like to record this computer's screen and audio
The prompt. Click Open System Settings.
System Settings with Stream AB Audio Helper switched on
Then switch Stream AB Audio Helper on.

Never saw a prompt?

It probably opened behind your DAW window - the helper has no Dock icon, so macOS does not bring it forward, and it is not in Command-Tab either. Minimise your DAW and look underneath. Or skip the dialog entirely: go to System Settings → Privacy & Security → Screen & System Audio Recording and switch Stream AB Audio Helper on yourself.

macOS 26: Stream AB Audio Helper is requesting to bypass the system private window picker
macOS 26 asks in stronger words.

On macOS 26 the wording is alarming - “bypass the system private window picker”, “personal or sensitive information”. It is the same permission. A request for system audio has no window to pick, so macOS routes it through the general screen-capture permission and describes the worst that permission could cover. The helper still takes audio only. If you would rather not, deny it - only the meters stop.

macOS: the helper may not be able to record until it is quit
Click Quit & Reopen.

If macOS then asks to quit and reopen the helper, click Quit & Reopen. The grant has not failed - it just only applies to freshly started processes. Your DAW is not involved. “Later” also works; the helper restarts itself within a minute.

When the meters don't read

What B's readout says instead of a number, and what each one means.

ALLOW SCREEN RECORDING

The permission has not been granted. If you never saw a prompt, it probably opened behind your DAW - see above.

HELPER OFF

The measuring helper is not running - usually just starting up. If it stays, reinstall the plugin.

NO AUDIO SOURCE

macOS found nothing to capture from. Rare; normally means no display is attached.

CAPTURE FAILED

The capture stopped. Switch away from B and back to restart it. If it repeats, tell me your macOS version.

-?? LUFS

Nothing measured yet - nothing is playing, or the panel is locked in the free version.

Also normal: B only measures while B is audible. On A its figure holds at the last value rather than dropping - that is deliberate.

Compatibility

macOS

  • macOS 11.0 or later - 13.0 for the reference’s meters
  • Intel and Apple silicon
  • AU and VST3
  • Tested: Logic Pro, Ableton Live, FL Studio, Cubase, Reaper, GarageBand

Windows

  • Windows 10 (1809) or later, 64-bit
  • VST3
  • Tested: FL Studio, Ableton Live, Reason, Cubase, Reaper

A/B, play, pause, skip and gain matching work everywhere, with every source. What varies is the track display and the meters.

On Windows both are uniform - the OS publishes a media API browsers report to, and audio loopback is built in.

On macOS, Apple restricted now-playing information in 15.4. Stream AB works around it and currently shows everything, everywhere tested. If a future update closes the route, the display narrows to Spotify and Apple Music - the switching is untouched, and the meters keep working since they measure audio rather than reading track data.

Whether a source honours a seek is up to that app - a browser tab’s scrub support depends on the page.

Questions

A/B switching, play/pause, the gain trim and interface scaling - every DAW, both operating systems, no account, and it never expires. The rest is the full version. The locked panels stay visible with a padlock, so you can see what is there.
No. It is one installer - paste your key into the settings of the copy you have and it unlocks in place.
No, and nobody signs into Spotify. The plugin asks the Spotify desktop app on your machine to play the track.
Yes - playback, transport and meters all work with any source. Only the in-plugin search is Spotify-specific. For anything else, start it playing yourself and Stream AB picks it up.
No. It mutes, unmutes, and applies the gain trim - nothing else touches your signal. The metering reads audio on the way past, produces numbers, and stores or sends nothing.
Because that is where macOS keeps system-audio capture - there is no audio-only permission. The helper takes audio only, nothing is recorded, and denying it only stops the reference’s meters. Detail under the Screen Recording section above.
macOS 26’s wording for the same permission. An audio request has no window to pick, so it routes through the general screen-capture permission and gets described in the broadest terms. The helper still takes audio only.
It almost certainly opened behind your DAW window - the helper cannot bring it forward. Minimise the DAW and look, or grant it directly at System Settings → Privacy & Security → Screen & System Audio Recording.
It matches a 3-second window, so it answers for the section that was playing - a verse and a chorus genuinely differ. Run it over the part you are working on.
Streaming services normalise playback, and your Spotify volume sits on top. Stream AB works from what you actually hear, because the job is a fair A/B, not matching mastered loudness.
The plugin can control playback but not read what it is. On macOS, re-enable the permission at System Settings → Privacy & Security → Automation. On Windows the source app probably doesn’t report to the system media controls.
Two machines per licence. Deactivate in the settings on an old machine to free a slot.
Anything that loads VST3, plus AU on macOS. The listed ones are just those actually tested. If yours misbehaves, tell me which.
Expected on macOS - unsigned builds count as new apps. Allow them again and it settles.

Still stuck

Email support@stream-ab.com. Your OS version, your DAW and what you were playing gets to an answer fastest.