"where if I switch the big chain to the lowest ring when I'm about to go up a hill" ottovaughn

Glad you have the problem figured out. Some friction shifters have the tendency to slightly loosen their friction with each lever movement (shift). Over time this loss of friction adds up to not be enough to hold the lever in place when the frame is being flexed (as in when adding up hill power). This was not uncommon prior to OS frame tubes and indexed shifting.

The above quote has me thinking (and wondering what is meant by big chain) that you might be riding up hill in the big big crossover combo. If so then I suggest trying another combo that will wear the chain less and be quieter. Crossover combos are fine to pass through but are more stressful on your equipment. Andy