DNA high sensitivity assay, strange ladder and marker

Dear Agilent team,

I've run this assay many times, but today I got a result I've no clue how to explain or where to begin troubleshooting.

The gel-dye mix is about 1.5 months; previous experience shows no major impact on the result. 

The ladder and other reagents were mixed well and stood at room temperature for over 30 minutes. 

Here's the result of ladder, and one of the samples (sheared DNA). 

(1) Ladder showed weird escalating baseline, 

(2) sample showed a steady baseline but missing lower and upper markers. 

I appreciate any suggestions or solutions.

Thank you in advance.

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