I finally got my serial card sorted, so I'm trying to get some devices to work. I installed my Denon amp and a CM11A yesterday and all seemed fine. Last night I tried to play a movie and my Denon was not responding. I opened a terminal and typed "dmesg" to see if my serial ports were all being recognized. Seems there is a problem. Here is part of the output from var/log/messages. This repeats over and over. I deleted the CM11A device that was using the D1 port. I also reinstalled the driver. Somewhere during my messing about and rebooting, the Denon started to work, but I'm still getting all these references to ttyD1.
Oct 14 08:06:39 dcerouter kernel: [75076.544586] XFS mounting filesystem sdb1
Oct 14 08:06:39 dcerouter kernel: [75076.753193] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:40 dcerouter kernel: [75077.777151] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:41 dcerouter kernel: [75078.779142] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:42 dcerouter kernel: [75079.792568] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:43 dcerouter kernel: [75080.793697] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:44 dcerouter kernel: [75081.816763] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:45 dcerouter kernel: [75082.505570] XFS mounting filesystem sdb1
Oct 14 08:06:46 dcerouter kernel: [75082.853319] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:47 dcerouter kernel: [75083.855263] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:48 dcerouter kernel: [75084.900651] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:49 dcerouter kernel: [75085.902643] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:50 dcerouter kernel: [75086.917194] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:51 dcerouter kernel: [75087.918317] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:51 dcerouter kernel: [75088.455561] XFS mounting filesystem sdb1
Oct 14 08:06:52 dcerouter kernel: [75088.919411] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0
Oct 14 08:06:53 dcerouter kernel: [75089.932475] No of Errors In ttyD1 brake=0 frame=0 parity=0 overrun=0