I went to the races today and had a problem that prevented me from racing. I have an sc10 with a spektrum sr300 receiver and the castle sidewinder sct esc motor combo. After building the truck I had an issue that shut the receiver off due to the castles sidewinder bec not being powerful enough, so I installed a capacitor spm1400 and that solved my issue. Now today I bought a y adapter and plugged in the capacitor and my laps transponder into the adapter. Apparently the capacitor wasn't strong enough for the transponder because with that plugged in I had the same issues as before I installed the transponder. Fortunately I had a castle external bec in my kit that i never used so i soldered on the bec and removed the red wire from the esc to receiver just like instructions said. The issue now is the throttle response is really rough. I hold partial trigger and the truck sits there and jiggles until I give it about half throttle. Wtf, I'm stumped. If I remove the bec and plug everything back In the way it was before today (capacitor only) everything is smooth and fine. Should I sell this castle junk and switch to the tekin rs ( which I have no issues with in my losi 22)? Please help.

Thanks