Testicle popping out of place?

Ok, I need some help.  This is something new to me.  My 10 year old sons gonad on the right side keeps "popping out of place".  He says it does this several times a day.  Tonight he showed me where he had a big "ball" right below his pubic line.  I have never heard of such.  My husband said he knows it happens, but this often?  Any insight you can give me on this would be much appreciated.

Thanks!

[BusyMom92960206]

Spoke with doctor.  This a not uncommon at all; as long as there is no pain.  Will continue monitoring through puberty, otherwise, no concerns.