Uncommanded exit game commands from I-Pac2 in AdvanceMAME

[alfonzotan]

I'm having a recurring issue with my multi-vector cab (https://forum.arcadecontrols.com/index.php/topic,168783.0.html):  after a game has been launched in AdvanceMAME, it will run for no more than about 15 minutes and then exit back to the front end (sometimes much less than 15 minutes).

I’ve isolated it to the I-Pac2 that’s installed.  I started with an I-Pac2 that had been on my spare parts shelf for several years, and then last week replaced it with a brand-new one, but unfortunately it’s also exhibiting the same behavior.  When I unplug the I-Pac from USB, games will run indefinitely, but with the unit attached games launched in MAME will always end and go back to the selection menu within 15 minutes or so (sometimes much sooner than that).

I’ve tried assigning the game exit command in AdvanceMAME to different keystrokes other than ESC, and moving the post the control panel's game exit button is connected to to different posts on the I-Pac board, but neither (or combinations of both) has fixed the issue.  I also tried this recommended fix today, but unfortunately, it doesn't correct the issue: https://forums.arcade-museum.com/threads/usb-dvg-users-support-thread.538841/post-4903748 .

The configuration is:

Raspberry Pi 5 4GB, the I-Pac2 is connected directly to the Pi with a 3-foot cable (I’ve tried two or three different cables, no difference I can discern in the behavior).
OS: Raspberry Pi OS 64-Bit v 5.1
AdvanceMAME, custom build for the USB-DVG vector generator (link to image here: https://drive.google.com/drive/folders/1KNNcKDJn_mh87HGbJHj9IvhJUWHlr3CX )

There’s also an Opti-Pac in this build, but I haven’t seen any issues with it connected.
The current game exit button is a repro Atari “volcano” button, but in a prior version of this build it had been connected to a standard leaf switch.  The button type doesn’t appear to make any difference.

I've been troubleshooting this for months now with no good solutions.  I’d appreciate any suggestions the BYOAC hive mind might have. 

[alfonzotan]

Update:  this glitch appears to be particular to the Pi 5 board and/or software build.  I ran a game on a Pi 4 with the image for that hardware for nearly an hour, and did not see this issue.

Some kind of weird interaction going on with the Pi 5 setup and the I-Pac.  I've reached out to Mario (software image developer) and also Andy at Ultimarc. 

[alfonzotan]

FWIW, I fixed this—as far as I can tell—by resetting the MAME Cancel_UI keystroke to a mouse click, and wiring my menu switch to the Left button post on the OptiPac that’s also installed in the same build.

For sure a work-around, but so far it appears to do the job.