Sounds like something is disrupting your serial communications somehow. At least ModemManager and GPSD might cause that when they probe for devices causing the device to react in unexpected ways when INDI driver tries to talk to them. Having the full driver debug log might show the issue, but you can also try uninstalling ModemManager especially if you don't need it. For GPSD you might need to somehow force it to ignore the ScopeDome port as from your log in the EQMod thread it seems you have a GPS device using another ttyACM port or you can try to rule that out by uninstalling or stopping GPSD temporarily too. And you should use the /dev/serial/by-id/ names for device ports avoid the ttyACM and ttyUSB names as the the order they are assigned numbers change randomly if there are multiple devices of same type, ie. a device that is ttyACM0 in one boot might be ttyACM1 the next and the device previously ttyACM1 becomes ttyACM0 depending on the order kernel discovers them. But the names in /dev/serial/by-id/ don't change and always point to the correct actual (ttyACM or ttyUSB) device.

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