I don't know if this topic has been touched upon already, but I was wondering how predictable it is for you all to have some kinf of spiritual attack before worship. For me, its so predictable that if it hasn't happened in the hours leading up to worship, it happens in the seconds leading up to it. Often times its emotional, but not always. A couple of weeks ago for example, I was hit with some really strong stomach cramps out of nowhere just before worship, I asked the Lord to lift them off me so that I could focus on leading, and He immediately did. Then last week, my guitar would not get into tune no matter what I tried and I spent 20 minutes trying to get it in tune (at home it had sounded perfectly fine), and so I ended up borrowing another guitar that sounded really discordant and was really hard for me to play.
This week, I was hit financially. I was preparing to print out song sheets when my computer's adapter cable connector suddenly broke, leaving me to have to rush to the store to buy a new $118 cable that I really didn't want to buy, something that would have normally really stressed me out had it not been for my prayers, and my alertness of impending issues leading up to worship.
So, in summary, its always something, and I believe its good to be alert and prayerful, and to have your friends pray in the hours or days leading up to worship as well. I have at least one friend praying for me because she has seen it happen and knows how predictable it is. The enemy just wants to use anything to keep you from leading others into the throne room, that is why we must be diligent to pray.