I am unable to adjust the multipoint red

NO, if red or blue will not adjust you need to replace both of the STK-392-120 convergence chips that this model uses.

There is a reason this happens.

The chips are black in color--2 1/2 inches wide X 1 1/2 inches tall with 18 pins each--they are mounted on two metal heat sinks on the board on the far left as you look from the back.

The back of each chip is metal and white grease to transfer heat quickly is applied to the back of each.
After some years the grease dries out and one of the chips overheats and fails.

There are if you locate the chips about a dozen light green resistors in front of the one towards the front of the set and to the left of it--they are all protection parts--all are 6.8 ohms. If any are discolored in the middle they need to be replaced along with both chips. They are easy to check--like checking a fuse--any that have NO reading across are gone.

Usually just both chips and a pair of the resistors need to be replaced and the set adjusted--I have done hundreds of these sets with this kind of problem

Considering that you can buy a pair of the chips on Ebay for less than 13 dollars plus shipping--if you or someone you know can do the repair--you can save the set and a lot of money--most shops get 300 or more for this kind of repair.

If you or someone you know can do it I will tell you what you need, how to get at the parts, and the best place to buy them.

The first step would be to look at the protection resistors to see or test if any are bad--do it with the set unplugged.

If you need help or advice, let me know--I am here to help people.

If this information has helped you, rate this solution as I DO THIS HERE FOR FREE.

SD TECH

it sounds like a remote problem check the batteries in it and see if they have full voltage in them.