The amount of oil is not an issue here, its a matter of your lifters are beginning to get "clogged" with oil deposits....You have 3 options to choose from to help quiet them down a bit...
Dissassmble your entire head, remove the lifters and throughly clean the holes in them free of any deposits, reinstall in reverse order. This method is not to time friendly, and if you don't have any mechanical experience, could get a little pricey depending on the shop charges. But since the head is apart might as well replace the lifters any who? -----> Option #2.
A method used by me when I had my 87 Jetta with noisy lifters... Run ATF fluid in place of the oil on idle for 10-20 min.
This may sound like a horrific thing for your engine, but its not...Just read on....
First drain all the oil in the car and either save if it is still good, or fresh. Then, add ATF fluid, yes Automatic Transmission Fluid, where the oil normally goes, right into the engine...All 4.2 quarts full, just like you were changing the oil. Run the car AT AN IDLE for 10-20 min depending on how noisy the lifters are. It is IMPERATIVE that you don't drive it with the ATF fluid in, it doesn't lubricate quite as well as oil.
Drain the ATF fluid out after it has idled for a bit, and replace with your oil. Voila! Your lifters should have quieted down to nothing!
The ATF fluid acts as a super detergent for the lifters and cleans everything out of there, with no harm to the motor at an idle, perfectly fine. My 87 Jetta had 204,000 miles on when I did this, and to this day, the motor is still running with over 260,000 miles on it.
So try that out, it should work. (sorry for being so long!)