As it happens so infrequently that will be a hard one to figure.
Are you able to run one system without the DDC? (what make model is it?) as that seems to be the odd item specific to your setup.
Perhaps (if any) others using a DDC can comment.
As far as 'putting down the iPad' causing dropout I would suspect RFI affecting a component (DDC?).
Perhaps hold the iPad near your setup and move it about in different orientations and see if you can reproduce the dropout.
Are you able to run one system without the DDC? (what make model is it?) as that seems to be the odd item specific to your setup.
Perhaps (if any) others using a DDC can comment.
As far as 'putting down the iPad' causing dropout I would suspect RFI affecting a component (DDC?).
Perhaps hold the iPad near your setup and move it about in different orientations and see if you can reproduce the dropout.
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bob
bob
