Sometimes the solution for this is really simple. Here are two things we never think about.
1) If you are using one viewer, try a different one such as singularity, alchemy, firestorm, or coolvlviewer.
2) Sometimes problems can be noticed when going between one os grid version and another grid version, if running firestorm, this problem is exacerbated if your router has DOS protection in the firewall settings. Denial of service protection stops large streams of data coming into your home network, but of course the viewers transmit large amounts during teleports and if your router sees this as a dos attack it will rate limit it or block it altogether, causing slow tp's and intermittent tp problems.