I have a inaccurate Beretta 92fs what do I do about this?

I have had this beretta 92 fs for about 2 years have only taken it out of the box a couple of times to shoot it. I haven't been to impressed with the accuracy that is why it doesn't come out much. I am wondering what is the best why to fix this problem? I have talked to my Gun Smith and my Gun Store Owner's but they all tell me the same thing " it's a Beretta 92fs it was built for nato not accuracy." But on the other hand if you go to Beretta's website they are really proud of this little potato. I have been shooting the same bullets, same weight, same powder,and in a pistol rest. The groups are about 8 inch at 15 yards in a inside range. I have tried to keep everything very controlled. Let me know if there is anything at all I can do with this 92fs, thanks guy's and gal's!