l
More likely due to poor component selection or poor quality components. Capacitors in power amps may het hot and if you look at the de-rating curves with increasing heat, you will see that many will only be rated for 1000 hours a elevated temperatures. Most caps are either 85C or 105C rated but of course running them cooler will extend the life considerably. Established brands like Panasonic, Nichicon, Vishay, Rubycon et al will work well within the spec as @agedhorse suggests above. However buy for reputable distributors.