Lately LCD modules showed up that do not comply with the unwritten standard that returning the cursor to home position on a non-shifted display will not take longer than 40 microseconds. The datasheet of the HD44780 controller chip clearly says 40µs up to 1.64ms, with the latter being common for un-shifting shifted displays. A display taking longer than approx 53µs for executing the home command, erratic behaviour will occur.
As the controller originally used in the Wave 2 does not know about shifting, the problem was solved by using a command to explicitely set the cursor position to 0 (zero) instead of the home command.
Here’s the result: