You say the computer does not go to sleep, yet there are programs pausing and waiting for input, unlike if it was just the monitor, the screen would go black but the video and audio would keep playing.
First thing, check those power settings in the Control Panel as you were told upthread. Make sleep/hibernate = never.
The only other thing I can think of is that the type of connection you’re using for the monitor is different than the old one.
If you changed the connection over to HDMI, that could cause some of these symptoms. HDMI is an audio AND video output. Make sure to check your audio devices in the Control Panel and if you have separate speakers plugged into sound port in back, switch over to that sound port as the default sound device.
If you are using speakers built into the monitor, then that’s probably the entire problem there. Once you use the Menu function on monitor itself to turn off sleeping, those should work fine.
Did not switch over to HDMI . I am using seperate Dell speakers which came with computer originally . I assume built in speakers are also working . Haven’t checked . I’ll try and do what you have advised . Computer in Japanese model so not so easy for me and the wife is not a computer wiz either lol .