Flashing green symbol

do you have ocram picons installed from the feeds ?.

another thing to try is in telnet

init 4 && opkg update && opkg upgrade && init 3

this will give you a read out of exactly what is being updated, as in the case of ocram picons as these can trigger the update icon without there being a full image update available.

Then try the telnet command, it will give a read out of what is being updated.