When using a slowcontrol frontend which operates a device using the multi class
driver the current midas version (ec3225902d6) has the following issue:

There is a row labeled with: All Input Output

So far by clicking e.g. on Input, only the Input related part was displayed, etc.

Currently this leads to the following error message: 

Error: cannot find key LS336/Variables/Input

where LS336 is my DD.