Did a workshop for 25 teachers today at my school, first day back from summer holidays. Didn't check ahead of time that SB was working properly (duh). Couldn't align the board properly no matter how many times I tried. SB pen wrote in jagged lines. Total disaster. Had to switch classrooms in the middle of the presentation to use a different SB.
After much web research and emails to email@example.com (who could not resolve the issue), I removed 2 screws underneath the ledge below the SMARTboard which apparently were causing some kind of magnetic disturbance. Now the SB works perfectly.