The latest and updated firmware of the extender works to improve its performance to the highest level. So, to update it manually, access your Linksys re6500 setup window and choose the wireless settings option. Further, click on the Firmware Update option and see the new version for your extender. Make sure to choose the exact model of your extender and download the original file on your PC. Afterward, click on the Firmware Update option again and wait till the PC completes the process. Once done, reboot the extender and check its performance as there will be a significant change in it.