Sounds like the loose nut is the problem, adjust the chain to have a small amount of slack, about 12mm up and down midway between sprockets, tighten wheel nuts making sure the wheel is central between chainstays, now nip up chain tugs. Try bike.
@ancientfixie started
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Sounds like the loose nut is the problem, adjust the chain to have a small amount of slack, about 12mm up and down midway between sprockets, tighten wheel nuts making sure the wheel is central between chainstays, now nip up chain tugs. Try bike.