If it isn't alarming you, and isn't accompanied by other warning signs of psychosis, e.g. Paranoia, confusion, or people telling you your beliefs are way off track, you may have nothing to worry about. Many people experience such things without being psychotic.

But I have been hearing that sort of thing for years and it really intensified before I began hearing clear voices.

The most amazing sounds were from an orchestra playing loudly in the middle of the night. I got suspicious when I found I could control what they played by thinking. That was during a manic episode.