Before you do, do yourself a favour and buy a can of [link=http://www.crcindustries.com/ei/content/prod_detail.aspx?S=Y&PN=02016]this[/link] first. After you've disassembled and checked all the connectinos, spray (sparingly) on all the pins on the receiver and servo/switch/extension terminations prior to reconnection. Don't forget the switch slider itself and battery junction.

Also, particularly if you're using an R700 RX, remove the RX crystal, and give the pins a light spray before replacing. Doesn't hurt to remove and give the TX crystal a spray as well. And it's a good cleaner for the TX aerial too. All our TX only output a pithy signal, so it's important the aerial be kept clean.