Do what I do: before you go to bed wash the earstem rubber with soap and warm water and pat dry with a towel. Takes 20 seconds and prolongs the life significantly. I had a slightly split pair of rubbers on a daily Rx frame that were used. I got 1 year out of those old rubbers before the split worsened and I had to replace the rubber. Not bad for an already split piece. Washing the oil off helps stave off the deterioration. Good luck!