If your DG was not new, I would suggest swapping the vac hoses on the AI and
DG. This may lead you towards a cracked line or fitting. I'm not an A&P or
any kind of Instrument Tech, but I can't imagine that applying low vac to a
new instrument would do it any favors. Just an idea.

Not snowing here (yet) but we've got a Winter Storm Warning from now until
Friday night. Now calling for 9-12" on top of the 18" we got last weekend.

Jim