Ableton Forum

Hello, community!

I wonder if anyone can advise me on a problem which cropped up last night (on stage at a show, of course).

1. SCENARIO:
1.1. Live 12.2 stops responding to specific APC40 MkII instructions.
1.1.1. Examples of lost functionality include Scene Launch, Stop All Clips, Channel Select
1.2. Other functions continue to behave as expected
1.2.1 Examples include Clip Launch, Channel Bank, Macro Controllers, Channel Stop Clip

2. SYSTEM DETAILS
2.1. Live 12.2
2.2. MPB 2023 M3
2.3. APC connected to mains powered USB Hub (not bus powered)
2.4. Also connected to hub:
2.4.1. MOTU MicroBook IIc
2.5. Configuration detailed above as performed as expected for a very long time.

3. STEPS TAKEN (SO FAR) TO REMEDY
3.1. Disconnect / reconnect USB Cable
3.2. Power-cycle APC
3.3. Quit & relaunch Live
3.4. Switch to a different USB port
3.5. Switch to a different USB Cable

4. RESULT OF STEPS TAKEN
4.1. No change in status from steps 3.1. - 3.4.
4.2. Step 3.5. (try a different USB cable) restored some lost functionality
4.2.1. Restored functions include Channel Select, Stop Clip (channel)

5. DESCRIPTION OF REMAINING PROBLEM
5.1. Global-type functionalities are still not being controlled by APC40 MK II
5.1.1. These include: Scene Launch, Transport Start / Stop, Stop All Clips -- anything that controls everything
5.2. Channel Bank up/down still functions as expected

6. THANKS! (...& a QUESTION)
6.1. Thanks to those reading through all of this for your time and consideration!
6.2. I was hoping to find some kind of "power-on reset" sequence for the APC40 but the documentation (read: its skimpy user guide) offers little in the way of troubleshooting suggestions. Are any of you all aware of any sort of "kick in the head reset" workarounds for the APC?
6.3. Thanks again!

Update to OP

7. FURTHER STEPS
7.1. Connect APC40 Mk II to Mac Studio Production machine
7.1.1. Different USB cable
7.1.2. Different Live set
7.2. Outcome: One more functionality restored
7.2.1. Global Stop / Start transport & "RTZ" (Shift + Start/Stop button) now work again
7.3. Still missing in action: Scene Launch, Stop All Clips (2 functions I use rather a lot, naturally)

Finally:

I haven't yet tried observing MIDI monitor output of problematic controllers, will look at that tomorrow and see if messages are being generated and what they are.

Thanks!

It might be midi mappings interfering. I’d check midi mapping.

If you use the APC explicitly as the default usage, you can turn off ‘Remote’ in preferences as long as it’s still set up in the Control Surface section. If you have some custom mappings for the APC, then leave Remote on.

Thanks!
If MIDI mappings are set-specific, the particular set that was problematic had no mappings associated to it. That's a bit strange because I almost always use a single mapping (l = toggle clip loop) and that one has been working without incident for quite awhile.

Another interesting aspect is this:
On my laptop, Preferences > Link, Tempo & Midi does not look the way it does on my Mac Studio production machine.

APC40 is indeed the default, and no check boxes (Track / Sync / Remote / MPE) are shown at all although the categories themselves are listed. (I guess this is because there are no other MIDI controller devices connected?)

Finally -- I just set the performance rig up, same as I always do, and everything is once again functioning as expected (...and if there's one kind of problem I really can't stand, it's an intermittent one). I will continue to monitor the situation, especially because I do have a full schedule of performances and recording sessions in the weeks ahead.

Thanks so much for your consideration, and welcoming any addition thoughts you have.
o99

Weird for sure.
Did you update anything recently (i.e before the show where it started happening)?

[jur] wrote: ↑

Fri Sep 12, 2025 1:48 am

Weird for sure.
Did you update anything recently (i.e before the show where it started happening)?

Thank you so much for your reply, and apologies for the delay in mine.
I've been on tour, with also several days of recording, and I'm only just now getting back to Matters Desktop.

To answer: No, I don't believe I updated anything... indeed, I discovered that my production machine (Mac Studio) is running an incrementally later version of Live (12.2.5) than the laptop (12.2) so I didn't even realize that there's a slightly later Live to catch the laptop up with.

The problem went away, but then recurred last week while I was out on the road.

I resolved it by swapping out the MIDI cable connecting the APC40 Mk II to the powered hub I use to run a couple of other peripherals (MOTU MicroBook IIc and sometimes a small keyboard).

It isn't the first time that switching out a MIDI cable has addressed this kind of problem, although it's a bit odd because I do really baby my cables. But... I guess, when it's time to go... it's time to go.

o99

otalgia99 wrote: ↑

Wed Sep 24, 2025 9:28 pm

It isn't the first time that switching out a MIDI cable has addressed this kind of problem, although it's a bit odd because I do really baby my cables. But... I guess, when it's time to go... it's time to go.

Glad you fixed it!

[jur] wrote: ↑

Thu Sep 25, 2025 1:19 am

otalgia99 wrote: ↑

Wed Sep 24, 2025 9:28 pm

It isn't the first time that switching out a MIDI cable has addressed this kind of problem, although it's a bit odd because I do really baby my cables. But... I guess, when it's time to go... it's time to go.

Glad you fixed it!

Oh, me too!

It's curious though -- I set this system up and strike it repeatedly in my home environment with no trouble, but on location? Suddenly the same components just love to cause trouble (and exactly where I need trouble the very least ;-> ).

I must test more rigorously to see whether or not the problems have any pattern.

Best regards,
o99

It might be sabotage! Your APC (or its cable) doesn't enjoy touring as much as you do

[jur] wrote: ↑

Mon Oct 06, 2025 7:03 am

It might be sabotage! Your APC (or its cable) doesn't enjoy touring as much as you do

An entirely understandable sentiment, and one which I might do well to meditate upon.

However -- in the absence of adopting such advanced levels of sanity, a fix has come my way courtesy of this most helpful youtube video: https://www.youtube.com/watch?v=7QDefNwx9D0&t=1212s

Rapid Flow (the presenter) mentions in passing that the two ribbon connectors in the unit become worn and that insulating them can restore global controls such as those which have been troubling me.

Two slim pieces of cardboard later, voila! Global controls are restored.... for now.

One of the commenters on the youtube page offered the fact that APC's have a lifespan of about 10 years (my unit is one month shy of that milestone). I can't verify the validity of that factoid, but the coincidence isn't lost on me -- I may well be playing a game of "Beat The Reaper" with this quick-fix, but I'll have to cross that River Styx when I get to it.

o99