Problem with Cell Washer

We have a problem with a Helmer Ultra CW centrifuge that we discovered yesterday.  When doing a quarterly check, we noted that when doing a "check" after a wash/decant/agitate/fill cycle, the cell button often does not always completely re-suspend.  Anyone know what might be the problem?

Helmer has had us check the settings and all seem as it should be.  This seems to be a random issue as sometimes it works for individual positions and sometimes it doesn't.  At this point, Helmer has not called back with anymore ideas.

Thnaks, Scott

Edited June 23, 20169 yr by SMILLER
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