Using MIDI Clock makes HX Stomp slow to receive MIDI EXP input

[TheCodeMonk]

Running Firmware 3.50.0, I normally send my EXP pedal to the stomp through MIDI (so I can also change it on the fly to use it on my other pedals).  This runs very smooth except when there's a MIDI clock sending constant data across the MIDI wire.  If there's a MIDI clock enabled from another device, the EXP pedal values jump and don't operate smoothly.  If I turn off the MIDI clock elsewhere, it runs smoothly again.  It's almost like the HX stomp can't handle MIDI clock and MIDI expression pedal info at the same time.

 

This happens even on an empty patch with nothing but the volume block I'm controlling.

 

Anyone else experiencing this?

[phil_m]

So are you saying you have the expression pedal plugged into this other MIDI device? What is that device?

[TheCodeMonk]

The midi chain right now is:

PirateMidi Bridge6 > DD-200 > RV-500 > HX Stomp > RC-10r

 

Expression pedal is plugged into the bridge6.

 

I can replicate the issue if I use the clock from the RV-500 or the clock from the Bridge6.  I’ve factory reset the stomp, reflashed the current firmware without restoring any new patches (I just updated the default first patch wah to use the midi cc controls for position) and it happens consistently with any kind of clock signal.  The minute I turn the clock source off, it’s back to smooth operation.

[PierM]

In my experience the HX Stomp doesn't really like busy MIDI while receiving clock, and EXP (continuous CC) can indeed unsettle the HX bus.

 

I've experience that a lot of times when trying to receive CCs from Zoia + clock, in fact I gave up trying to feed it with any external clock and at the opposite, I'm using its own clock as master for the other devices on my pedalboard. This kind of solved the problem; the HX clock isn't the best I've seen in terms of jitter tho.

 

 

 

 

 

[TheCodeMonk]

On 3/28/2023 at 1:18 AM, PierM said:

In my experience the HX Stomp doesn't really like busy MIDI while receiving clock, and EXP (continuous CC) can indeed unsettle the HX bus.

 

I've experience that a lot of times when trying to receive CCs from Zoia + clock, in fact I gave up trying to feed it with any external clock and at the opposite, I'm using its own clock as master for the other devices on my pedalboard. This kind of solved the problem; the HX clock isn't the best I've seen in terms of jitter tho.

 

 

 

 

 

 

Good to know I'm not the only one who has experienced this...was worried I had a defective unit or something.  Probably count it as a bug and file a bug report in case there's anything a L6 engineer can poke at.

 

I find it struggles even if it's not configured to obey the external clock...just feeding it on the MIDI channel at all seems to make the EXP messages jittery.  Since my planned source is my MIDI controller for everything, I would have to run a separate MIDI wire from it to the stomp, different than everything else and configure the clock to not send to the one output.  Frustrating.  Ah well.

[PierM]

On 3/28/2023 at 6:13 PM, TheCodeMonk said:

I find it struggles even if it's not configured to obey the external clock...just feeding it on the MIDI channel at all seems to make the EXP messages jittery.  Since my planned source is my MIDI controller for everything, I would have to run a separate MIDI wire from it to the stomp, different than everything else and configure the clock to not send to the one output.  Frustrating.  Ah well.

 

Have you tried to apply a MIDI monitor to that data? I would give it a check to see what's exactly happening at every stage. Maybe you can tame the problem filtering useless information, or hijacking stuff to different channels.

[TheCodeMonk]

On 3/28/2023 at 9:42 AM, PierM said:

 

Have you tried to apply a MIDI monitor to that data? I would give it a check to see what's exactly happening at every stage. Maybe you can tame the problem filtering useless information, or hijacking stuff to different channels.

I did use MIDI monitor to find the root of the issue, which was a clock signal.  There's only the clock signal and expression messages being sent to the HX stomp.

[Andreas0815]

Reproducable even with firmware 3.60. 

 

Sometimes the CCs get processed immediately, but at times there is a freeze of 5-10 seconds and suddenly the CCs get processed in fast forward, like if the processing took so long. Could be hint for a software issue in the midi processor of HX, resulting in an overload if too many messages arrive in short time?

 

In my setup there is Midi over Bluetooth in the signal chain, so I have to check the signal flow before the HX first and will postvthe results here.

But I remember a similar problem in old firmware versions with midi CCs over midi cable from Zoia.

 

Looks like there is no midi message filter to protect an overload to me. Thanks im advance! :)

 

Looking forward to a statement from Line6 to this issue.