I recently upgraded from KDE 11.4 to 12.1 64bit. After I leave my PC alone, the screen saver comes on, but when I attempt to reactivate, I only get a blank screen no matter what I do on the keyboard, so I have to hard reset. I tried the screen saver in test mode, but there is no stalling!

Then I turned off the screen saver. After I leave my PC alone too long, S2R activates, then I attempt to reactivate and it stalls to a blank screen again. I have to hard reset. Then when I do S2R manually then reactivate later, there is no stalling!

It seems my PC does not want to be left alone, but sometimes I cannot help it. I tried looking for errors with this:

Code:
linux-ppnb:/home/randolph # tail -n 200 /var/log/messages
(snip)                          
Jan  4 14:33:00 linux-ppnb kernel: [ 1975.397496] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep                                    
Jan  4 14:33:00 linux-ppnb kernel: [ 1975.398461] xhci_hcd 0000:03:00.0: WARN: Stalled endpoint                                                
Jan  4 14:33:00 linux-ppnb kernel: [ 1975.399041] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep                                    
Jan  4 14:33:03 linux-ppnb kernel: [ 1978.402061] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep                                    
Jan  4 14:33:03 linux-ppnb kernel: [ 1978.403061] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep                                    
Jan  4 14:33:03 linux-ppnb kernel: [ 1978.403990] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
Jan  4 14:33:03 linux-ppnb kernel: [ 1978.405004] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
(snip)
Jan  4 14:33:30 linux-ppnb kernel: [ 2004.457628] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
Jan  4 14:33:30 linux-ppnb kernel: [ 2004.458646] xhci_hcd 0000:03:00.0: WARN: Stalled endpoint
Jan  4 14:33:30 linux-ppnb kernel: [ 2004.459450] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
(snip)
Jan  4 14:33:50 linux-ppnb kernel: [ 2024.504437] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
Jan  4 14:33:50 linux-ppnb kernel: [ 2024.505383] xhci_hcd 0000:03:00.0: WARN: Stalled endpoint
Jan  4 14:33:54 linux-ppnb kernel: [ 2028.506528] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
(snip)
Jan  4 14:34:37 linux-ppnb kernel: [ 2071.585394] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
Jan  4 14:34:38 linux-ppnb dhclient[2564]: DHCPREQUEST on wlan0 to 8.6.48.39 port 67
Jan  4 14:34:38 linux-ppnb dhclient[2564]: DHCPACK from 64.9.229.97
Jan  4 14:34:38 linux-ppnb dhclient[2564]: bound to 64.9.242.184 -- renewal in 245 seconds.
Jan  4 14:34:41 linux-ppnb kernel: [ 2075.588173] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
(snip)
Jan  4 14:34:49 linux-ppnb kernel: [ 2083.609720] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
Jan  4 14:34:49 linux-ppnb kernel: [ 2083.610561] xhci_hcd 0000:03:00.0: WARN: short transfer on control ep
I'm not sure what this is talking about. Please give me clues as to how to dig out this problem. Thanks in advance.