Debian Wheezy USB2 ehci_hcd

Question

Eu tenho um amigo que decidiu mudar para o Linux do Windows. Eu a estava ajudando a levantar e correr o mais rápido possível, mas nos deparamos com um problema que não consigo resolver.

Ela usa o Debian Wheezy, instalado a partir da última imagem de CD de instalação do XFCE ( dd em um pendrive). Tudo correu bem e seu sistema funciona quase completamente.

O único problema que ela tem é que alguns de seus pendrives não estão funcionando. Eles podem ser mounted (tanto pelo root quanto pelo automount do xfce), mas a leitura da unidade gerou timeouts, dmesg mostrou que ehci_hcd continuou redefinindo os dispositivos usb2.
Como uma correção, eu rmmod ed o ehci_hcd módulo do kernel e os dispositivos começaram a funcionar, mas eles eram muito lentos.

Como outra solução possível, atualizei o kernel da caixa para o que está em wheezy-backports , que é 3,10, mas o problema ainda persiste. Verifiquei as configurações de BIOS , mas elas também precisam estar em ordem.
As unidades funcionam no meu laptop e as portas usb funcionaram com o sistema operacional anterior, portanto, não é um problema de hardware.

Eu fiquei sem ideias o que mais eu poderia fazer para consertar a caixa dela.

Veja a saída de dmesg do erro atual:

[ 3694.256023] usb 7-2: new high-speed USB device number 5 using ehci-pci
[ 3694.388813] usb 7-2: New USB device found, idVendor=1e3d, idProduct=2095
[ 3694.388818] usb 7-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 3694.388821] usb 7-2: Product: Flash Disk      
[ 3694.388823] usb 7-2: Manufacturer: Generic 
[ 3694.388825] usb 7-2: SerialNumber: CCBB0201160720281014278106
[ 3694.389132] usb-storage 7-2:1.0: USB Mass Storage device detected
[ 3694.389234] scsi9 : usb-storage 7-2:1.0
[ 3695.388487] scsi 9:0:0:0: Direct-Access     Generic  Flash Disk       5.00 PQ: 0 ANSI: 2
[ 3695.388770] sd 9:0:0:0: Attached scsi generic sg3 type 0
[ 3695.389346] sd 9:0:0:0: [sdb] 3911680 512-byte logical blocks: (2.00 GB/1.86 GiB)
[ 3695.389970] sd 9:0:0:0: [sdb] Write Protect is off
[ 3695.389973] sd 9:0:0:0: [sdb] Mode Sense: 0b 00 00 08
[ 3695.390591] sd 9:0:0:0: [sdb] No Caching mode page present
[ 3695.390595] sd 9:0:0:0: [sdb] Assuming drive cache: write through
[ 3695.394223] sd 9:0:0:0: [sdb] No Caching mode page present
[ 3695.394228] sd 9:0:0:0: [sdb] Assuming drive cache: write through
[ 3695.395392]  sdb: sdb1
[ 3695.401344] sd 9:0:0:0: [sdb] No Caching mode page present
[ 3695.401350] sd 9:0:0:0: [sdb] Assuming drive cache: write through
[ 3695.401354] sd 9:0:0:0: [sdb] Attached SCSI removable disk
[ 3710.357646] FAT-fs (sdb1): utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive!
[ 3710.380122] FAT-fs (sdb1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
[ 3741.008027] usb 7-2: reset high-speed USB device number 5 using ehci-pci
[ 3751.252026] usb 7-2: reset high-speed USB device number 5 using ehci-pci
[ 3767.496024] usb 7-2: reset high-speed USB device number 5 using ehci-pci
[ 3767.744027] usb 7-2: reset high-speed USB device number 5 using ehci-pci
[ 3777.988055] usb 7-2: reset high-speed USB device number 5 using ehci-pci
[ 3778.120554] sd 9:0:0:0: Device offlined - not ready after error recovery
[ 3778.120586] sd 9:0:0:0: [sdb] Unhandled error code
[ 3778.120589] sd 9:0:0:0: [sdb]  
[ 3778.120591] Result: hostbyte=DID_ABORT driverbyte=DRIVER_OK
[ 3778.120593] sd 9:0:0:0: [sdb] CDB: 
[ 3778.120595] Read(10): 28 00 00 00 00 42 00 00 ce 00
[ 3778.120602] end_request: I/O error, dev sdb, sector 66
[ 3778.120619] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.120688] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.120690] sd 9:0:0:0: killing request
[ 3778.120724] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.120740] FAT-fs (sdb1): FAT read failed (blocknr 34)
[ 3778.124088] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.124269] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.124282] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.124292] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.124302] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.124311] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.124366] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.124377] sd 9:0:0:0: rejecting I/O to offline device
... This repeats a lot of times, then ...
[ 3778.126304] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.126314] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.126323] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.126408] sd 9:0:0:0: rejecting I/O to offline device
[ 3778.126415] FAT-fs (sdb1): FAT read failed (blocknr 34)