Judder/stutter RPi3 on LG TV

Hi, Im new to this forum so I hope I can find some help.

I have a RPi3 with last version of LibreElec 9.2.1 Leia 18.6 installed. Today I noticed I can activate the adjust the refresh rate to make the image smoother on my TV.

I have a LG 32LB5800-ZM with 3 HDMI ports, first it's ARC, the second is normal and the last is MHL. Im not interested to use ARC or MHL so Im connected to HMDI 2.

HDMI CEC is working fine because it has Simplink activated.

At 1080p 60hz the image looks perfect but when the refresh rate is activated and it gets adjusted to 50hz for PVR channels or 24hz for movies the image quality looks terrible!

There're many sharpy edges, the colors are very saturated and I also get overscan. When I stop the video everything gets to normal.

On the MHL port I don't get any of this problems but the refresh rate stills 60hz even if my TV shows the image is running at 24hz or 50hz. On the other ports I get the same problem but the refresh rate is working perfect.

I don't have other TV to test if the problem is on my RPi3 or the TV.

I hope somebody else has a similar LG TV to help me, thanks

EDIT : It seems the TV is the problem, when the refresh changes it detects the RPi3 like another device. I pressed the Q.MENU button while something was playing and I marked the Image format as "Only scan(Translated from spanish)". Now it changes the overscan automatically and the refresh rate works perfect on PVR and movies. The only little problem is with the colors... I use the preset for Sports color which it looks perfect on the UI, now I need to use Standard preset and the colors are a little light but no big deal.

For me is solved and maybe this can help other LG users

My bad, Im using 9.2.1 with 18.6. I also edited on 1st post. Thanks for repply

EDIT: The overscan happens only when I play something, when I stop the video everything gets back to normal. The overscan is visible on the video and also on the UI.

EDIT 2: It seems the TV is the problem, when the refresh changes it detects the RPi3 like another device. I pressed the Q.MENU button while something was playing and I marked the Image format as "Only scan(Translated from spanish)". Now it changes the overscan automatically and the refresh rate works perfect on PVR and movies. The only little problem is with the colors... I use the preset for Sports color which it looks perfect on the UI, now I need to use Standard preset and the colors are a little light but no big deal.

For me is solved and maybe this can help other LG users