mount usb másodikra

Üdv!

Egy Fedora 21 x64-en egy 64GB-os pendrive (új állapotú, vfat fs), csatlakoztatás után csak másodikra hajlandó mountolódni.
Azaz csatlakoztatom, "mount /mnt/usb" után hiba nélkül visszaadja a promptot, de nincs bemountolva. Mégegyszer ki kell adnom a "mount /mnt/usb" és ekkor használható.
A dmesg-ben nincs hiba, selinux permissive:
[ 6794.869520] usb 2-1.1: Product: DataTraveler 3.0 [ 6794.869523] usb 2-1.1: Manufacturer: Kingston [ 6794.869526] usb 2-1.1: SerialNumber: 0019E06B0840BF21C75F1E44 [ 6794.870820] usb-storage 2-1.1:1.0: USB Mass Storage device detected [ 6794.873117] scsi host5: usb-storage 2-1.1:1.0 [ 6795.968413] scsi 5:0:0:0: Direct-Access Kingston DataTraveler 3.0 PMAP PQ: 0 ANSI: 6 [ 6795.969420] sd 5:0:0:0: Attached scsi generic sg2 type 0 [ 6797.397152] sd 5:0:0:0: [sdb] 122915328 512-byte logical blocks: (62.9 GB/58.6 GiB) [ 6797.397879] sd 5:0:0:0: [sdb] Write Protect is off [ 6797.397887] sd 5:0:0:0: [sdb] Mode Sense: 23 00 00 00 [ 6797.398492] sd 5:0:0:0: [sdb] No Caching mode page found [ 6797.398502] sd 5:0:0:0: [sdb] Assuming drive cache: write through [ 6797.430239] sdb: sdb1 [ 6797.433266] sd 5:0:0:0: [sdb] Attached SCSI removable disk [ 6799.602081] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null) [ 6799.602095] SELinux: initialized (dev sdb1, type ext4), uses xattr [ 6804.712921] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null) [ 6804.712937] SELinux: initialized (dev sdb1, type ext4), uses xattr [ 7434.832319] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null) [ 7434.832331] SELinux: initialized (dev sdb1, type ext4), uses xattr [ 7455.708605] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null) [ 7455.708621] SELinux: initialized (dev sdb1, type ext4), uses xattr [ 7473.183358] usb 2-1.1: USB disconnect, device number 6