Hi

I have just bought a new Gaggia Classic + MDF. I have installed them and tried a couple of shots. So far they're a bit sour (but I'm no expert).

I thought I'd check what was the water temperature as it existed the brew group, and after 10mins of warm-up I get around 72C (Using a meat thermometer and milk thermometer) See Video 1.

The "Ready" light is also flickering sometimes, with a faint electric spark sound, like some wire was exposed and mis-connected. See Video 2.

Now, what should I do about those things? Am I even measuring the temp correctly?

Videos available here: http://img839.imageshack.us/g/ddl.mp4/

You are not checking the temp properly.

Use the styrofoam cup method.