DA not following guidelines

I am trying to modify an order for CS from '94. My five kids are pre teen & teens now & it costs more than the $200mo I've been getting. Also I just lost my job this summer which really makes things tight.
Now after I filed with the FS office (we're in a small town & my ex is a county official) their DA says my ex is offering $75 more mo.
I brought up what I'v learned, thinking the Ca guidelines should give the kids between $400-$900mo since I have them 60%, him 40%. My ex tells the DA I'm getting money from a trust which I'm not & have proven more than once but they won't pay attention.
A paralegal aquaintance told me he talked to an attorney who said I should counter offer $300mo plus 1/2 actual child related expenses. I don't know if that's fair either because if I don't have $$ in the first place even if he pays 1/2 of what I buy, I won't be buying much. How can they do these types of things? I thought they were suppoed to be working for the kids best interest.

If he is a county official, ask for a change of venue on those grounds!!! Get a decent attorney and sue his @$$ for what your children deserve!!

I hate those people who use their positions to influence others in court. IT'S NOT RIGHT!

There is one problem, $$. That's why I filed the OSC for modification myself instead of gettting an attorney. The only way I can see it is to max out my credit cards & then where does that leave me?
I think the problem is someone else established a trust for the kids tuition at private school & my ex wants the $$ instead. My opinion but everything he's said against me or done the last 7+yrs sure makes me think so.
the trust did get the kids an attorney but she told a paralegal friend of mine that the Family Support DA was giving my ex counsel and offered me $275mo instead of the $200mo I've been getting. She supposedly suggested that I ask for $300 plus 1/2 of actual out of pocket expenses for the children., Still seems like we're getting the short end of the deal and everyone else is getting the $$