mc wrote:
I'd look for bad splices first. Beyond that, telephone
wire
really isn't suitable for speaker connections. Each of
your 4 wires
is (approximately) 22-24 AWG. When you bundle them
together, they
may be close to 14 AWG in overall size, but they won't
have the
current carrying capacity of a real 14 AWG wire made if
many very
tiny strands.

My understanding is exactly the opposite -- that separate
strands (of
the correct total cross sectional area) are better than a
single
wire.

Unfortunately, yetther old wife's tale.

(1) Speaker cables aren't generally large enough to have
appreciable losses in the audio band due to skin effect.

(2) Stranding the wire doesn't reduce the diameter of the
conductive part of the wire. Even insulating them makes no
difference, because skin effect is based on magnetic
coupling, not conductivity.