The numb hands are especially odd of you are as relaxed as you say. Where is the numbness? Does it feel like it's from pressure.
Numb hands are either from too much weight on them (either bad fit or tense arms) or (extremely rarely) pinched nerves or blood vessels from your position. If you're DEFINITELY ruling out the bad fit and tense arms...
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If once a man indulges himself in murder, very soon he comes to think little of robbing; and from robbing he comes next to drinking and Sabbath-breaking, and from that to incivility and procrastination.
- Thomas De Quincey