100 Mb/s speed using cat6 cabling

[The Sloth]

I wired some cat6 cables in a few parts of the house and when a friend came over to help me terminate the cables to a patch panel and to the keystone jacks, he mistakenly used cat5e keystone jacks and a cat5e patch panel. Now i'm finding that some connections are operating at 1Gb/s while some are only operating at 100 Mb/s. Are the cat5e keystone jacks and the patch panel the problem here? Do I need to replace these with cat6 rated equivalents in order to get 1Gb/s speeds throughout? Did I get lucky with a few connections that managed to run at 1Gb/s? The keystone jacks are not hard to replace but the patch panel would take some time to re-do.Thanks for your help!