If you haven't already try dropping tension as well, for my dense pattern Prestige rackets BHB7 really feels great strung in the high 40s. Anything higher than that though feels too control oriented. I don't get any major arm issues at that tension range either. I string BHBR a little higher to control the pop, usually mid 50s.
2 YTK Prestige Pros w/Tourna Big Hitter Silver Rough 48/45lbs; 2 FXP Prestige MPs w/Tourna Quasi-Gut 60lbs