Fender Deville C4 has resistor added, is this a mod??

[ENB]

My amp tech died earlier this year and I have been crash coursing in getting up to speed doing my own maintence. While in my Hot Rod Deville, I noticed that C4, a small electrolytice cap (cant read value as it is turned) has a 26k resistor jumped parrallell to it, I assume to create some type of pass filter. I no he did some tweaking on the amp, and the reistor looks like it has definately been added at a later date than ori. manufacturing. Any Ideas on what the purpose would be for this if it was a mod?

Thanks

ENB