There are a couple of things you could still try. If you're a bit handy with a soldering iron you could knock up an RX noise cap, rather than a power cap using a 100nF and 10nF cap across the power rail to see if that combats the noise from the BEC
http://www.maplin.co.uk/p/multilayer...apacitor-dt98g
If there isn't a ferrite in the output of the CC BEC you could try winding the output lead around one
http://www.maplin.co.uk/p/ferrite-ring-hem3016-qt26d
http://blog.oscarliang.net/wp-conten...ritering_2.jpg
These are fairly cheap solutions before you give up all hope
Ian