zmc abnormal exit status 255

[jc9876]

i am running ubuntu 16.04 ltc and zm 1.30.4 i configured it to switch from monitor to modect by cron with: zmpkg.pl <name>. After switching the xmc -m <m#> continually restarts with said error. this error continues for an hour then everything works well. rebooting after the switch makes no dif - it stil takes about an hour. any thought/