I’ll agree that it looks like watering issues. It could be inconsistent or overwatering leading to cell damage in the leaves, though I wouldn’t rule out root rot or pests since watering issues can invite both. If you are really concerned, you could repot with fresh potting soil and inspect the roots for damage. Wipe the top and bottom of the leaves with a damp paper towel and look for pests just in case.

I think you can find it for sale on AliExpress by searching for ‘Topton N100 NAS motherboard.’

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