I agree with GrammaRocks. In California, employers don't want to mess around with Child Support Enforcement when it comes to wage garnishments. They are responsible for getting the payments in and notifying the Child Support Division if the employee is working less hours, etc.
At least here, child support isn't considered late as long as it's paid on the last day of the month. It then gets processed by the "registry" which can take a few days. As long as the support is being paid within the month, regardless of when you receive it, the employer isn't late and is adhering to the order.
Another thing to consider is that you may want your child support on the first of the month or by a certain day, but the employer can only deduct support from actual earnings. The employer isn't obligated to write you out a check on a certain day. The money is deducted from payroll. They can't send you what he hasn't earned yet. And, I believe, they can only take a certain percentage at a time. I'm a little surprised that the employer would even be contacted if there have been no arrearages in 8 years.
I'm a single mom. I've had support orders that I learned early on I couldn't count on. Yes, I needed that money, but I worked to take care of my kids and child support was icing on the cake. I couldn't worry that I wouldn't be able to pay my bills on time if I didn't get child support by a certain day. Or EVER.
I don't mean any offense, and I know all to well how frustrating it can be, but it doesn't sound like the employer is in violation of the orders. They may be jerks and wait til the last minute, especially if they are being bugged throughout the month for 8 years, but it sounds like you are getting child support each month. That's no too bad.
Just my opinion.
Best wishes.