Having trouble w/the esc w/glitching after 50-70ft....

... I checked all soldier joints, ok, moved cc bec away from reciever, checked motor leads , ok. After taking esc out of buggy, I found that the on/off switch wires were fraying at the point where they were soldiered to the board. Could that cause the prob.?
Do I need any special soldier to re-soldier wires to the board?
1. MBX-6 T8 1900KV, RX8 ON 4S
2. MBX-5T 1520, MMM ON 5S
3. MBX-5 ONROAD CONVERSION 1515, MMM ON 5S
4. MRX-3 ON ROAD CONVERSION 1512, MMM ON 6S
5. TEN T 2650 T8, MMP ON 3S