I would try updating to 1.13 since that was released today.
I personally haven't any connection issues with my PS3 on 1.12 or 1.13 (with the limited usage so far). Under 1.12 I've been able to run Warhawk and MGO servers or play regular rounds with some light torrenting on my MacBook Pro. I can also stream 1080p PSN movie rentals without issue. I've only had 1.13 installed for a couple of hours, but Warhawk has been running without issue so far.
I run wired with a static IP if that helps at all.