faint precession of sound on vinyl


On some records during some quiet passages you can hear the faint traces of upcoming sounds softly precede their emergence. Has anyone noticed this? What is this effect?
chashmal
If it was the stylus reading the signal on the adjacent wall wouldn't it change channels? I notice it is always on the same channel it is preceding.
Deaf_j...The playback stylus does not "read the adjacent wall". It is reading its current groove, but that groove was corrupted by the adjacent groove when the record was cut.

As to which channel is affected...it is horizontal groove modulation (mono) which is the problem. (Vertical groove modulation doesn't affect groove spacing). So, the pre-echo signal will be the mono component of the next groove.