[Kingprinter]

Does pulling in and out hp jackplug affect its contact quality undefined

 

[John Reeves]

The answer is no it does not affect the contact, in fact the reverse. When you plug it in and out it cleans the contact surface which can have a film build up over time. This applies to all plugs. In addition, do not use a silicon based furniture cleaner in the same room as high end equipment as a film can build up on interconnects. This was the subject of a debate a few years ago in high end stereo mags.
One proviso, if you have a Zen Xtra try to plug headphones in and out as little as possible as the connector is prone to failure.