Fuel pump loud

[BR3W CITY]

So I took the truck back out on the road for the first time this year today, and all went well, tho I did notice some noise from the fuel pump at one point.

My fuel setup used to be a 255 and earls filter, and has always seemed fine. At this point it was a combination of -8 and -6 coming to some 3/8 hard lime.

Just this year, I switched the -6 out for -8 from tank to hard line, and changed out the fuel pump bracket to sit about 3/4" higher and be a bit more out of site.

On the drive, we heard a loud mechanical wine, much harsher than the usual "fish tank" motor sound the pump usually makes. The pump was not hot to the touch, and the noise only changed slightly when revving or idling. We checked our tank, which was about 1/2 full, maybe a tad less.

We drove to the nearest gas station about 1.5 miles away, and when we pulled in, the noise had gone completely back to normal (no fuel added yet).
Put more gas in it, just to have a fresh tank, and have heard to noise since...

So what do you think? A fluke one the first run, or maybe just some air in the line....or something more nefarious? I'd hate to think the fuel pump was dying already. The pump is a few inches above the sump, but it's worked fine and I was told by the rep' that the draw was not too much for the pump. Hmmmm