How can I get my vinyl trampoline clean?

New-to-me Hobie 16 has a vinyl yellow trampoline covered in tiny flecks of black (mildew I'm assuming) after sitting outside for several years. Have power washed and tried several cleaners (mildew & mold, bleach, non-bleach) with no success. Any recommendations?

1) Think of it as 'patina' rather than mold.
2) Instead of cleaning it, sail the &#!z out of it!

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Jerome Vaughan
Hobie 16

Plastic bristled scrub brush with Ajax and some elbow grease.

I always find that no matter how stubborn the dirt/stains on the tramp are, usually at least 90% of them seem to be gone after long day of sailing and sitting out in the sun.

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