Enhanced resolution with PCSX-ReArmed not working

[thrasher]

Hello,

I've recently installed 9.2.3-PULSTAR on my Raspberry 3 A+ and enabled the enhanced resolution from the in-game menu in the PCSX-ReArmed emulator as indicated in many tutorials.
The graphics however do not change after activating
the option (tested with Metal Gear Solid (E) (Disc 1) [SLES-01370]), neither reloading the game nor restarting the emulator.

I've seen some posts saying that enhanced resolution may not be working depending on the version of RB, depending on whether it's 64 or 32 bit platform, it might be the ROM etc.

Could someone please clarify and provide info on which HW/build combination it's supposed to work?

Is there any setting in RB itself that needs to be changed (I've started out from factory settings) that I need to tweak first?

Thanks for helping!

Robert