Intermittent MIDI rx issues

Just to add

our setup is MSC triggers via Qlab firing a specific Cue List/Cue number. 

what's your setup connection wise? MIDI cable, usb adapters, network...

Response MIDI Gateway on the lighting network, MIDI cables out of that into a Playtec USB MIDI Junction II on the sound end. 

ionRPU master and IonXe20 backup

qlab4

Does the Playtec have basic indicators when it sends out a message?  
Does this happen with specific cues, or could it be "any cue" / "at random"?
If you re-run a missed cue, does it get to Eos and run correctly?
Is the Response MIDI plugged into Eos via USB or over a network?  How far is it from the Playtec device from the Response Gateway? (MIDI standard describes that it must be less than ~25')

Hi Matt

it appears randomly however we have only noticed this at a house opening - MIDI check into preset - and subsequently the MIDI cues in the show have no issues. 
when the cue is re-run (within 30 seconds) MIDI runs correctly without turning MIDI RX off/on. 

the setup has been in place over a year with no changes (and no problems). The only recent change was updating eos to 3.1.5. 

Hi Matt

it appears randomly however we have only noticed this at a house opening - MIDI check into preset - and subsequently the MIDI cues in the show have no issues. 
when the cue is re-run (within 30 seconds) MIDI runs correctly without turning MIDI RX off/on. 

the setup has been in place over a year with no changes (and no problems). The only recent change was updating eos to 3.1.5. 

We haven't made any changes to Show Control connections between 3.1.2 and 3.1.5, so it would be surprising if updating to 3.1.5 from a slightly earlier version would make a difference.

I suggest that the next time you notice this happen, press [Displays] + [Record] to put a "pin" in the software logs.  Confirm that the next set of MIDI messages work, then save off the logs and post them here so we can have a look at them for you.  Alternatively, you could email them to me directly at mattp at etcconnect.com.