Device Inventory shows old data

I have a 100E running 5.6.3.  I use the Device Inventory on a pretty regular basis to help detect rogue devices, but I'm noticing a lot of inaccurate/old data in the list.  A lot of devices have odd descriptions, and inaccurate OS listings (Laptops showing as NAT devices, servers showing as Unknown devices, Win 10 showing as XP, etc.), but the big problem for me is that a lot of the Windows PCs are being listed with outdated host and user names.  Even when I reformat a hard drive, rename the host, and have a new user logging in, the device shows up with all the old data. I have tried deleting the device from inventory hoping it will correct itself when it rediscovers, but all the old data comes right back - and sometimes with odd device descriptions again.  Is there any way to force a refresh, or clear a cache, or something?

Thanks