Scuze me?
..tiny letters.. mine might be an actual pos then because it's definitely in vibe mode. At any rate I haven't had the same experience.. and my bass has great sustain so can't blame it on that. It doesn't respond very well in the practice space. Maybe it's too sensitive. I'd try it here solo but I left it in the case turned on apparently and it's dead atm.
In all seriousness, if the guy who gave it to you really is guitarded as you'd say, perhaps the tuner saw a little bit of abuse.
Most tuners don't really like being dropped, hit, tossed, or the like. If he gave it to you new in the box, just take it to a dealer to get it swapped or call Snark:
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