Until someone do atleast 1000 testing rolls, it's hard to say there is a "randomize" issue, but nearly everybody feel there is one so I guess it something to investigate.
Random doesn't really exist in a computer program, it's always related to a "real data", the common one is the actual time when the "random" number is generated, but depends on used code it can be easily badly done.
There is a big difference between feeling there is something wrong and the game having issues on randomness. This is the tricky part with probabilities.
[video:youtube]
https://youtu.be/MEewLWDpscA?t=1507[/video]