This sound like the same issue some folks are having with UML290 on a Mac. The posted solutions supposedly work when you are in a 4g area however they do not work when in 3g. Does anyone (verizon?) have any info on this? This modem is 4g/3g compatible correct?
See my post in response to '4G on the fringe'. I'm using a UML290 in a Nexaira BC2 and it rocks (coming from Sprint 3G anyway). I followed the tips on evdo forums, locked my modem to LTE and now working from home over VPN every day is much less painless (I occasionally drove in just to get a decent network, I don't see that much anymore - at least until the smartphones come out and people start trashing 'my' tower).
I have an MBR1000 router from Cradlepoint and a UML290 modem from Verizon. I have firmware 1.9 installed on the router. I found out that when I use the 5 volt power supply that came with the router the UML290 modem will not stay connected to a 4G network. If I use a 12 volt car type power source the modem does stay connected.
You worried me a little so I looked. My Cradlepoint MBR1000 came with a 12 volt 1.5 Amp output and 110 volt input power supply. Try to get Cradlepoint to give you a new one.