Thanks for your input & feedback, all!
Actually I think this may finally provide me with a long-awaited
excuse to acquire an ESR meter!
Any recommendations for a good but readily available one for casual use?
I was suspicious of that big-butt Samwha cap based on its ratings... but it
looks healthy enough. Maybe I'll pull it out & check it, or just hit 'n' hope & toss in a replacement and see what, if anything, happens