We just purchased 8 managed switches POE to swap out our existing in preparation for our new phone system. We installed them all after configuring with static IP. Deployed... and all but two work fine. Can someone assist with tips for troubleshooting why two of them do not work? There are a couple other switches in the building. Could it be that a switch "upstream" from the two non-functioning switches is causing an issue? If so, how do I find out? When we put back the two "dumb" switches all was fine. Any tips to help would be much appreciated.