Purring and rumbling

Question
hello, I have a young male guinea pig, about 5 months old. He is constantly purring or rumbling, im not entirely sure of the difference. Anytime we speak to him or pet him he goes very low, purrs and swings his hips. I have heard this may be a dominance thing, but is it a negative behaviour? He used to mount our hands alot but not so much anymore. Sometimes he just rumbles without swinging his hips.

I would appreciate any advice you could offer me, im very confused. Thank you.

Answer
This is an easy question.  He is communicating to you.  He probably wants to be help and played with.  So enjoy!  When he purrs @ you answer him with the same vocalization.  You can do a search and find out what the different sounds mean.  Basically, he just wants more interaction.  Go ahead play, watch TV together, snuggle!  Have Fun!  Cindy