Ext Midi clock emits slow clock, burn in and latest firmware



I’ve been trying to use my Flxs1 after a while not using it. I’m trying to sync it to my digitone using midi in- and it seems to sync ok but the clock out to other modules is beats rather then /24.

Is this by design or a bug?

What’s the latest stable firmware? Maybe I need to update?

Also, I notice my screen is looking a bit funny now - I suspect some burn in since it;s been powered on in my rack for a quite a time without much use. Anything I can do about this?



If you are syncing to your digitone, I would reccomend using the digitone as the MIDI clock source.

When your device boots up, it gives you a firmware version. 20b6 is the latest currently

You can download the latest firmware here:

Your OLED may be experiencing burn in. The newer firmwares have a screensaver mode which helps with this. The OLED can also be replaced. If the screensaver doesnt help, then let me know.



Hi Tenkai!

Thanks - I’m trying the firmware update and have a couple of questions…

When I insert the usb cable should something happen? I don’t see anything on the flxs1 screen or on the computer. I am using a mac with teensy 1.52.

When I drag the hex file into the teensy app i notice it says this at the bottom

flx1_20b6-1-g9bf59ef.hex (too l <- does this (too l mean something?

When I press the PGRM button nothing happens.

Thanks , Tom


ok I changed cable and I think has flashed ok now - I am seeing blue zizag lines on the screen – I guess this is the screensaver!

However, the clock out seems to be the same. Is that normal?

It is syncing ok with the digitone, but the clock out from FLXS1 is on the beat, not /24. So when I sync my other sequencer is far too slow. Is there a way to configure the clock out rate?


When you plug it in, nothing should happen. The teensy loader should show the name of the hex file (make sure its the unzipped hex). If you press the PGRM button and nothing happens, there are a couple things to try -

  • make sure the green auto button is bright green. click it if it is dim
  • a different USB cable - really, this is a very common fix. Not entirely sure why!
  • re-download teensy loader and try with a new fresh version.


nice! glad you could get it to flash.

There is no way to configure the MIDI output. Unfortunately, this is one thing I have had a hard time getting to work properly. I would highly recommend to use the digitone as the clock source, and then use a MIDI splitter to sync other devices, or use the midi thru on your other devices to connect to your FLXS1.



I don’t mean the midi output, I mean the clock output - bottom right beside cv4b.

I am trying to clock another eurorack sequencer from FLXS1 - in this case TINR Tuesday.

If I use the internal clock of the FLXS1 and set to 120bpm - the clock output (not midi out) is flashing fast. I think 1/24.

If I use the 35m ext midi from digitone at the same 120 bpm - the clock output is running much slower. 1/4.


Ah, yea gotcha.

This is also not configurable unfortunately. I am starting to work on a new software update, and this is def high on the list.

For now, you could use a CVB output with a square wave LFO, or use one of the track outputs and turn on every gate for that track, and use the gate output.


yeah I think it would be better if it sent the same rate as it would if it was using internal clock.

ok I shall try your suggestion for cvb square wave. thanks.

Also - s there a way to send a reset signal via cv or midi out?

If you are working in that area - I would consider making midi out configurable as a reset trigger output. That way Flxs1 can act as a nice bridge between external synths and other down stream euro sequencers.

Thanks for responding so quickly!

All the best, Tom


oh that is an interesting idea… I hadn’t thought of it. I am not sure the MIDI output would be capable of driving analog gate inputs, it might need to be buffered in order for that to work…


Afraid I have no idea of the technicalities :wink: but it would at least make use of that output which is probably otherwise unused.

Failing that - being able to use a CV outs for reset would be useful.