X17 XCLUSIVE - MTV Asked Spencer Pratt "To Hit His Sister On Camera," Says Source

Sources close to Heidi and Spencer Pratt say the reality couple is fuming at MTV for the network's "inappropriate requests and lies" ...one request involving family abuse.

A friend close to Spencer tells X17online exclusively:

"MTV has been asking them to do inappropriate things for the show. They've wanted Spencer to play up his aggressiveness for ratings, and he doesn't want to do it. For Season 5, MTV producers even asked Spencer to hit his own sister Stephanie."

The drama doesn't stop there! X17online has also learned that "a female producer in Season 5 shoved Heidi from behind and that pissed off Spencer. When he confronted that producer, that's when MTV said Spencer threatened the producer. She was supposed to be fired, but was allowed back as a producer for this season."

Seems as though the Pratts aren't feeling the love on set from co-stars either. Friends say Kristin Cavallari has been publicly bashing them - claiming they're no longer filming this season of The Hills.

Our source denies these claims telling us:

"Heidi and Spencer are definitely part of the this season, just not much considering the circumstances. Kristin Cavallari has been making comments about them because she is just jealous. Heidi is doing a movie with Jen Aniston and Nicole Kidman and Kristin's new movie went straight to DVD."

As for the Heidi's lawsuit against The Hills' executive producer Adam Divello for sexual assault ... it's still "100% on." MTV hasn't yet commented on the most recent allegations, but they've already told X17online that the lawsuit is "completely false and without merit."