it has something to do with your broadband speed.
pc/laptops seem to handle xbmc a bit better but it also crashes on my pc sometimes, on 10mb speed.

xbmc is more sensitive to the connection stability and speed than other apps like cloudtv or hitv, in my experience.
it crashes whenever the data flow is unstable or too slow coming, won't wait long to buffer.

if u installed frodo 12.3 correctly, no need to reinstall anymore.
if using wireless, try wired, it works better.
if too many addons, disable or uninstall some of them as they tend to slow things down when there are updates.
try modifying the cache size (my earlier post) to incr buffer, will help - but this will require some work.

hmm... getting curious...

can you tell us what broadband and speed r u on?

q5ii wired or wireless lan?