My (generally slow response) HR21-100 has started to randomly lock up on occasion. Doesn't happen too frequently, but enough to be annoying. Have not noticed this at all on my (fast, responsive) H20. Any thoughts on where to start? I recently had a dish alignment reset and the guys swaped out the LNBs, but I can't recall if started before or after their visit. In any case, since it doesn't happen to the H20 I was assuming it's not related to that. Thoughts?