Great question — answering as the UphillTech team:
First you should activate the "thorough rinsing" option on your machine (if it has one). Modern washing machines seem to be manufactured mostly for the ads and less for the actual washing they're supposed to do. "Saving water" sounds good in ads, but if a washing machine rinses your clothes in too little water, there'll be residue of detergent or lint left in your clothes. Most machines give you an option to either use more water during the rinsing step or to insert an additional rinsing into the cycle. Then you should read the service manual of your machine and do all the maintenance steps it describes. Those usually include cleaning lint filters. Be sure to have some old or dirty towels...
Full answer by Elmy: https://lifehacks.stackexchange.com/a/24749 (CC BY-SA 4.0).
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