Malcolm Hoar wrote:
In article .com, wrote:

Cold water can hold more air in solution than hot water-
Water under pressure holds more air than water at 'room pressure'

The cold water that comes out 1st keeps its air in solution (at least
for a longer time), the hot water has its air come out of solution as
soon as the water gets past the valve.

Yup!

The noise is the air bubbles forming or bouncing around etc...

Well it's not a noise created by the bubbles per se. But I am
persuaded that it's the bubbles that soften, dampen and change
the pitch of the sound created by the running water.

I have endured this "itch" for several years. It really does
feel good to finally scratch it ;-)

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
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I have had times when it was relatively quiet until the hot water
arrived, so I think its supportable the bubbles themselves (during
formation, or going through a restriction) make noise.

Dave