I'd also been having this issue with my new samsung STB... after 18 months of no issues at all with the pace box.
Initially I thought it may be a problem with the samsungs themselves as many had posted issues with them too.
When my samsung was installed I asked the engineer if the samsung would be ok to place back above my dvdplayer in my cabinet as I had with the pace stb. He said that the samsungs ran cooler and there would be no problem with this.
I have found that they are cooler than the pace boxes but from what I can tell crash more often at lower temperatures.
I know this becuase I would get 3-4 crashes a day where my internet would stop working but my tv would still be on.
Since moving the stb out of the cabinet it runs much cooler and hasnt crashed once in about 4 days. So its either heat cuasing the issue or by some very strange coincedence ntl fixing it at the same time I took it out of my cabinet.
Well its something to try anyways....