[MELB TRAM] Buzzing Noise (Xmas Spirits!)

[njpc@ozemail.com.au_NOSPAM]

Since it's that time of year, ie the Xmas party season:

Some trams have a high-pitched buzzing noise that varies in pitch and
volume as the tram accelerates and decelerates.  It seems to come from
one of the overhead compartments and (I guess) is related to engine load
or something similar.

The point is, you're sitting on the tram in the morning with the mother
of all hangovers and all you want to do is sit there and sleep, or, at
least, impersonate a stunned mullet.  Instead, this bloody annoying,
whining, buzzing noise goes up and down as the tram jerks back and forth
as the driver stops and starts and I'm thinking, "Will I make it to my
stop, or do I throw up over the blonde opposite or the suit next to
me?".  And still that noise goes straight through your head and pierces
your brain!!

What is it, and what can we do about it, apart from taking to the
compartment with a sledgie?

Sufferingly,
Nick.