Serious playback problems (error 80710092 / 800288D8 and DNS

[psxgamer]

I’ve been having huge problems with my PS3 and/or PS3 Media Server lately. Problems seem to lead to DNS and other networking issues, but I cannot be sure are these related to PS3 or the PSM.

The playback is interrupted any time with a errors like 80710092 and various errors regarding DNS. I tried to change the DNS names to Google’s DNS and various others, but the problem remains. When a DNS error accurs, Playstation 3 is also logged out of PSN Network. The firmware is the latest version (4.31).

Errors like 80710092 or 800288D8 occur all the time. Sometimes PS3 plays the movie 20 minutes, other times 40 minutes. Sometimes only a few minutes. For instance, in this log you can see that the lates playback was interrupted by 800288D8 error (2012-11-24 21:07:07.422 on log 24_11_2012). Then when I try to restart the playback a network error 80710092 occurs. If I restart Playstation 3, the playback starts again until the next error. Other similar case on 27_11_2012_log at 21.21 when it just says that the playback is interrupted. PlayStation 3 also signs out of PSN Network after the error. Once I restart the console, everything works fine –for a while.
Log and various other files can be found here:
https://dl.dropbox.com/u/8869063/24_11_2012_debug.log
https://dl.dropbox.com/u/8869063/27_11_2012_debug.log
https://dl.dropbox.com/u/8869063/PMS.conf

I have a 1Gbit Ethernet cable connected to the D-Link DIR-655 router and PS3’s IP address is set to firewalls DMZ setting. Computer is equipped with Intel Core Duo E8500, 6Gt RAM and Win 7 64-bit. I uninstalled and reinstalled Java (Version 7 Update 9 32-bit) and PS3 Media Server 1.72 with a fresh installation (by deleting the config file of PSM). These seemed to help a little bit with the problem, byt did not fix it (just occurs a little bit less now).
Nothing seems to fix this issue. Is there any way of making sure is the problem with my Playstation? When I have tried to google this issue, I often notice that people claim these Playstation units are faulty. My unit is a 40Gb old fat model. Should I just buy a brand new model?

[psxgamer]

I went to the recovery menu on Playstation 3 and did a "Restore PS3 system" -option. It wipes all data and clears everything.

Did not help though, same problems re-accour.

[chocolateboy]

There are no errors in either debug.log. It's unlikely to be a PMS issue.