If you want any updates on this issue, or would like to report updates, feel free to message me and I'll post it here, or post in the comments.
The Playstation 3 version of the game has been plagued by freezing issues since the last update. It seems to occur mostly while joining a session that is mid-heist. Starting your own room or joining one before the heist starts does not usually lead to freezing, though this is unconfirmed. For some this issue can be rare (once every couple of days) or extremely common (every time you try to join a heist). For myself it is the latter, making the game almost unplayable.
This issue is known by Overkill, as seen here. Still, the last known acknowledgement of this problem is from September, and there has not been a new update since.
Possible fixes
These are completely unconfirmed, and only suggestions from community members. So far I have not been able to try most of these, so take them with a grain of salt:
- Remove Payday 2 from your PS3 and redownload it.
- Free up space on your hard drive. A lot of players report getting freezing when free space is under 5GB.
- If you own a physical copy, delete the Game Data Utility and redownload the update.
- Delete save data and settings (REALLY DO AT YOUR OWN RISK)
- Play the game in 520p instead of 720p. I am not sure how this is action is performed.
- Faster internet speed. Many report that freezing issues occur only during online heists. Using a wired connection may help, though this has been tested by myself and freezing issues still occur.
- Cool down the PS3. Some believe that this is caused by an overheating issue (despite that no other games are affected by it) so place your PS3 in a cool spot, or maybe use a third-party fan to cool it down.
For a greater idea of the scale of these issues, google "Payday 2 PS3 freezing," it is incredibly common.