Custom Post Type Query in Sidebar incl. Custom Field Data

Hey everyone,
I would like to output a list of posts in my sidebar, the posts in that list are belonging to a custom post type called “concerts”, so far so good. Problems occur when i add the code necessary to output custom field values assigned to the single posts in the “concerts” post type, shouldnt it be possible to just loop through the posts and simply output those custom field values within the loop?

This is how it looks by now… Any hint is greatly appreciated!
Thanks…

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