Take a piece of rubber band and cut it . Take the rubber band and lodge it between the two strings just before and after the qianjing. I've tried it and find that it takes away some noise. Your Erhu will sound slightly cleaner, but some of the edge in the tone is lost. You decide.
Here's how it looks like:
Ok, I'll like to add another picture. This is the original idea from Claude. A rubber band just below the qianjing instead. I added the rubber band above the qianjing as well in the original picture because I saw Mr SYR put a piece of cloth in between the strings just above the qianjing for noise reduction.
It sure looks neater.
