USB mount problem

Hi All
I have flashed my Dreambox 800hdse with blackhole 3.0.1. Initialised a USB (top port on back) and used it for flash expander which is working according to the check. I install ipk files to temp folder via FileZilla (autobouquet e2 28.2, crossepg, cool TV guide, linuxsat panel) then install separately vi BH IPK Install app. I then install mgcamd 1.35a etc. All works fine, but when I try to mount a second USB to hold picon files on, it will tell me to reboot, but will get so far then go into standby from then on, I press standby to boot and does the same thing again. PLEASE HELP!
Thanks Simon