#5658 NORM Ship.2: Sticky Alt or Control Key

[Zarro Boogs per Child]

#5658: Sticky Alt or Control Key
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  Reporter:  davidpfarrell  |       Owner:  wad      
      Type:  defect         |      Status:  new      
  Priority:  normal         |   Milestone:  Ship.2   
 Component:  hardware       |     Version:  Build 650
Resolution:                 |    Keywords:           
  Verified:  0              |    Blocking:           
 Blockedby:                 |  
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Comment(by frankprindle):

 Eureka! I have 3 rather significant pieces of info for wad which may help
 in the investigation of this problem:

 1) After 3 days, I got tired of waiting for the stuck Alt to return
 spontaneously, so I shut down the machine, folded it up, tossed it into
 the front seat of my car, covered it so it wouldn't get stolen, and left
 it in the parking lot at work for about 6 hours at 30 degrees F (temps
 today in the Philly area). When I brought it inside after driving home, I
 put it back on the bench, powered it up, and sure enough, the Alt key was
 sticking rather badly, letting me get only one or two other keypresses in
 before coming on again. So the problem is exacerbated by the cold (sorry
 whoever baked theirs, you went in the wrong direction.) Surely 30 degrees
 F is not outside the environmental limits for the H/W.

 2) Now that the problem was occuring, I could test various things. The
 most significant finding was that I could unstick the Alt key by either
 pressing it, OR... by pressing firmly on the white plastic directly below
 the Alt key (without depressing the Alt key at all.) It is still that way,
 about 1.5 hours after bringing it back indoors (temp about 67 degrees
 here). I don't know when/if it will go away again. In any case, this
 clearly points to a "mechanical" rather than an "electrical", "firmware",
 or "software" issue. The white plastic should be quite inert in any of
 those last 3 categories.

 3) Now that the Alt was sticking rather regularly, I used mini-tamtam to
 test various letter and number keys. Although the sticking Alt would alter
 the pitch, none of the letter or number keys would ever stick themselves
 (thus sustaning a note), in spite of what is indicated in the on-board-
 diagnostic. Thus, I conclude that, while the diagnostic is fine for
 showing what IS sticking, it is useless for showing what IS NOT sticking -
 i.e. it shows keys sticking when in fact (when running with the linux
 driver) they do not. The subject of another (much less critical) ticket
 I'll submit once all this gets squared away.

 So I will be calling for my RMA tonight. I hope these bits of info are
 useful in helping wad and the other developers to eliminate the problem in
 manufacturing that is causing this. Will replacement units be thoroughly
 tested to ensure they do not have this defect? I'm assuming the
 replacement unit will come with its own 90 day warranty, right?

 Thanks

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Ticket URL: <http://dev.laptop.org/ticket/5658#comment:61>
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