The driver \Driver\WudfRd failed to load

Thanks for checking so quickly. 

A few more questions if you do have a chance to look into this further:

1. Was the Windows Driver Foundation service was "Manual (Trigger Start)" rather than just "Manual"?  The first will allow the service to startup automatically if a device is connected.
2. Do you observe this usually after a reboot with the card reader(s) attached? 
3. If you restore the startup type for the Windows Driver Foundation service to "Manual (Trigger Start)",  stop the service, then unplug/reinsert the card reader(s), does this also result in event ID 219?
4. If you go to Device Manager -> Portable Devices, do you see a node for your card reader(s) without any errors?  There should be one per drive.

The answers to these questions will help identify whether this is a card-reader timing issue, a driver loading issue, or a timing issue with the startup of the service & detection of the card reader(s).

As you noted, the event ID 219 is okay to ignore if the card reader is still functioning properly (i.e. accessible from Explorer), and if you are not trying to use Windows Media Player to sync media to the storage cards.

I ran command (PowerShell Admin) unfortunately got an empty text file

As stated above changing Windows Driver Foundation from Manual to Automatic will temporarily "fix" this part of the problem BUT Windows tends to reset this back to Manual.

Also as stated above this occurs on two completely unrelated machines (HP-Desktop & Acer-Tablet) and I doubt that I have two machines with same error.

This is the latest Event log for Event ID 219 

Log Name:      System

Source:        Microsoft-Windows-Kernel-PnP

Date:          11/13/13 1:35:28 PM

Event ID:      219

Task Category: (212)

Level:         Warning

Keywords:     

User:          SYSTEM

Computer:      Michael-HP

Description:

The driver \Driver\WudfRd failed to load for the device SWD\WPDBUSENUM\_??_USBSTOR#Disk&Ven_Generic&Prod_USB_SD_Reader&Rev_1.00#18E3312D81B&0#{53f56307-b6bf-11d0-94f2-00a0c91efb8b}.

Event Xml:

<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">

  <System>

    <Provider Name="Microsoft-Windows-Kernel-PnP" Guid="{9C205A39-1250-487D-ABD7-E831C6290539}" />

    <EventID>219</EventID>

    <Version>0</Version>

    <Level>3</Level>

    <Task>212</Task>

    <Opcode>0</Opcode>

    <Keywords>0x8000000000000000</Keywords>

    <TimeCreated SystemTime="2013-11-13T18:35:28.143306800Z" />

    <EventRecordID>49464</EventRecordID>

    <Correlation />

    <Execution ProcessID="4" ThreadID="220" />

    <Channel>System</Channel>

    <Computer>Michael-HP</Computer>

    <Security UserID="S-1-5-18" />

  </System>

  <EventData>

    <Data Name="DriverNameLength">124</Data>

    <Data Name="DriverName">SWD\WPDBUSENUM\_??_USBSTOR#Disk&Ven_Generic&Prod_USB_SD_Reader&Rev_1.00#18E3312D81B&0#{53f56307-b6bf-11d0-94f2-00a0c91efb8b}</Data>

    <Data Name="Status">3221226341</Data>

    <Data Name="FailureNameLength">14</Data>

    <Data Name="FailureName">\Driver\WudfRd</Data>

    <Data Name="Version">0</Data>

  </EventData>

</Event>

Which I imagine is related to Event ID which I get for DR1 to DR4 which are part of the Multicard Reader referenced in 219 above.

Log Name:      System

Source:        disk

Date:          11/13/13 1:00:35 PM

Event ID:      11

Task Category: None

Level:         Error

Keywords:      Classic

User:          N/A

Computer:      Michael-HP

Description:

The driver detected a controller error on \Device\Harddisk2\DR2.

Event Xml:

<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">

  <System>

    <Provider Name="disk" />

    <EventID Qualifiers="49156">11</EventID>

    <Level>2</Level>

    <Task>0</Task>

    <Keywords>0x80000000000000</Keywords>

    <TimeCreated SystemTime="2013-11-13T18:00:35.640486700Z" />

    <EventRecordID>49382</EventRecordID>

    <Channel>System</Channel>

    <Computer>Michael-HP</Computer>

    <Security />

  </System>

  <EventData>

    <Data>\Device\Harddisk2\DR2</Data>

    <Binary>0F00800001000000000000000B0004C0030100000000000000000000160000000000000000000000D9FD040000000000FFFFFFFF06000000580000050000000000000612280108000000000073000000000000000000000040D1BA0100E0FFFF0000000000000000B0B4E90100E0FFFF000000000000000000000000000000001B000000010000000000000000000000000000000000000000000000000000000000000000000000</Binary>

  </EventData>

</Event>

On an affected 8.1 machine, the following powershell script will output the Windows Driver Foundation-related Windows Error Report (WER) events into a text file (werUmdfReports.txt):

PS:> get-winevent -providername "Windows Error Reporting" | where-object {$_.Message -like "*wudf*"} | format-list | out-file werUmdfReports.txt

LOTS of people are getting this error in the Event Logs for card readers. It's CLEARLY a Windows 8.1 problem, so it would be good if Microsoft could confirm that a fix is in the pipeline.

As you say, though, the hardware appears to be working fine. I've tried every card reader slot on my computer and they all work OK, so I'm just ignoring the  Event ID 11 errors for now.

Just to update the situation I'm getting this same Event ID 11 regarding DR1 on a second unrelated computer. So HP Desktop Windows 8.1 (64 bit) Acer Iconia W500 Tablet (32 bit) NEITHER of which had this error PRIOR to Windows 8.1 UPGRADE but now BOTH have the error.

Obviously something changed with the upgrade I'd ignore the error BUT am trying to resolve ALL the errors caused by Windows 8.1 and hopefully that will solve the more serious problem of my computer not being able to automatically go to sleep.