New noises from old Burnham

I have a 1984 99k input Burnham boiler supplying about 50 linear feet of base board. Two Honeywell zone valves.

Some new noises while burner is on recently, best described as a creaking or muffled pop coming from the boiler.

As far as I can see nothing external has changed.

Pressure is about 14 psi in two story home.

Hydrostat 3200+ digital control killing burner at 190.

No visible leaks.

Doesn't seem to be taking makeup water.

No air coming out of air separator, but if I remove the red cap it will drip water, don't think its clogged.

Relief not popping.

Temp differential on expansion tank in about same location as always ,(about a 1/4 of the way up).

Grundfos Alpha set on auto, reads 0 gpm and 7 watts with one zone calling, as always.

We did lose power for 7 hours during the last storm but outdoor temps didn't drop below 25 and house was heated with 36k gas fireplace,

Been in this home 25 years, very reliable unit, is there a need to worry or have something checked?