At Thermostat

1. Fan was on Auto
2. Cooling was On

Outside Unit was making noise. Outside Unit Fan not coming on at all

Next to the compressor on the Wall there was On Off Switch, I turned off power from the outside unit but it still kept making that noise

I went inside turned off the Cooling and noise went away

It has two capacitors 30uf and another small one 5uF

Unit is Lennox

1. Is the issue with my capacitors?
2. Can i replace these two capacitors with a single 35uf one ?
3. Or i am thinking it completely wrong and it's something else?