External thought stream??

["setiamon" <setiamon@...>]

Upon practicing one-pointedness excercise for hours i'v noticed a
strange accurence after long periods which is after the inner thoughts
fade a new stream of thoughts seem to emerge that seem to be not my own
and do not dissolve like my own,i had been repeatidly frusterated by
this as it seems after the background thoughts dissolved i would
achive onepointedness(focal thought or visualization to the exclusion
of all others) but this other stream comes that seems to be completly
unrelated to my own mind/being such as conversations that have nothing
to do with me,voices from people i don't know,images of places i have
never been to 
and general chaos that seems completly unrelated to me
and only dissolves after breaking the attempt to sustain focus on the
target.I previously mentioned this in "excercise clarification" I
became so frusterated i Reread IIH again and found something that
sounded a bell in me,bardon said after awhile thoughts will seem to be
coming from afar and intruding into ones mind!I immediatly checked
various sources and people and was basicly told that this was indeed
external,that the mental body was receiving static basicly from the
mental plane,is this true?someone told me bardon puts lots of blinds
in his book to seperate the "Worthy" from the "unworthy" is this
true?Is this a fork in the road 
and which how do i find myself to the onepointedness state from
here?how do i shut off this external stream if it doesn't seem to
decay or be empowered by my own mind?