[Sony Tablet S] vladok:
Yes, I have already tried several firmware installations.

This is the log you requested:

Starting recovery on Mon Oct 7 08:26:38 2013
can't open /dev/tty0: No such file or directory
framebuffer: fd 3 (1280 x 800)
recovery filesystem table
=========================
0 /tmp ramdisk (null) (null) 0
1 /hwconfigs ext2 /dev/block/mmcblk0p1 (null) 0
2 /configs ext4 /dev/block/mmcblk0p2 (null) 0
3 /system0 ext4 /dev/block/mmcblk0p3 (null) 0
4 /system1 ext4 /dev/block/mmcblk0p4 (null) 0
5 /cache ext4 /dev/block/mmcblk0p5 (null) 0
6 /misc emmc /dev/block/mmcblk0p6 (null) 0
7 /staging ext4 /dev/block/mmcblk0p7 (null) 0
8 /blflags ext4 /dev/block/mmcblk0p8 (null) 0
9 /datapp ext4 /dev/block/mmcblk0p9 (null) 0
10 /log ext4 /dev/block/mmcblk0p10 (null) 0
11 /data ext4 /dev/block/mmcblk0p11 (null) -32768
12 /sdcard vfat /dev/block/mmcblk1p1 /dev/block/mmcblk1 0
13 /boot emmc boot (null) 0
14 /recovery emmc recovery (null) 0
15 /system ext4 system (null) 0
16 /vendor0 ext4 vendor0.img (null) 0
17 /vendor1 ext4 vendor1.img (null) 0

Command: "/sbin/recovery"

ro.boot.serialno=015d32205e300c0d
ro.boot.commchip_id=0
ro.boot.bootloader=0x00000009
ro.bootmode=unknown
ro.baseband=unknown
ro.bootloader=0x00000009
ro.hardware=txs03
ro.revision=0
ro.factorytest=0
ro.secure=1
ro.allow.mock.location=0
ro.debuggable=0
persist.sys.usb.config=mtp
ro.build.id=TJS0166
ro.build.display.id=TJS0166
ro.build.version.incremental=130329002
ro.build.version.sdk=16
ro.build.version.codename=REL
ro.build.version.release=4.1.1
ro.build.date=Fri Mar 29 00:51:21 JST 2013
ro.build.date.utc=1364485881
ro.build.type=user
ro.build.user=integ-build
ro.build.host=build5
ro.build.tags=test-keys
ro.product.model=SGPT12
ro.product.brand=Sony
ro.product.name=SYS_052
ro.product.device=txs03
ro.product.board=txs03
ro.product.cpu.abi=armeabi-v7a
ro.product.cpu.abi2=armeabi
ro.product.manufacturer=Sony
ro.product.locale.language=en
ro.product.locale.region=US
ro.wifi.channels=
ro.board.platform=tegra
ro.build.product=txs03
ro.build.description=SYS_052-user 4.1.1 TJS0166 130329002 test-keys
ro.build.fingerprint=Sony/SYS_052/txs03:4.1.1/TJS0166/130329002:user/test-keys
ro.build.characteristics=tablet,nosdcard
ro.opengles.version=131072
wifi.interface=wlan0
wifi.wpa_supp_ready=0
persist.tegra.nvmmlite=1
ro.sf.override_null_lcd_density=1
keyguard.no_require_sim=true
debug.nfc.fw_download=false
debug.nfc.se=false
ro.ril.wake_lock_timeout=200000
ro.streaming.video.drs=true
ro.tether.denied=true
ro.sony.sound.enabled=true
ro.sony.irremote.devicefile=/dev/ttySIR0
ro.sony.autovolume.threshold=10
ro.product-res-path=vendor/framework/SemcGenericUxpRes.apk
ro.sony.update.server=info.update.sony.net
ro.sony.update.category_id=ST001
ro.config.alarm_alert=Alarm.ogg
ro.config.notification_sound=Notification.ogg
ro.config.ringtone=Ringtone_XPERIA.ogg
ro.carrier=unknown
drm.service.enabled=true
dalvik.vm.heapstartsize=8m
dalvik.vm.heapgrowthlimit=64m
dalvik.vm.heapsize=384m
ro.semc.enhance.supported=true
ro.semc.clearaudio.supported=true
ro.somc.dmnorm.supported=true
ro.sony.wifisleep=0
ro.sf.lcd_density=160
ro.setupwizard.mode=DISABLED
ro.com.google.gmsversion=4.1_r4
ro.com.google.clientidbase=android-sony
dalvik.vm.dexopt-flags=m=y
net.bt.name=Android
net.change=net.bt.name
dalvik.vm.stack-trace-file=/data/anr/traces.txt
tf.enable=y
ro.sony.wan.ipv6.enable=false
persist.sys.sony.cabc.disable=0
persist.sys.sony.hdmi.disable=0
ro.sony.cradle.settings=true
ro.sony.hdmi.settings=true
ro.sony.cabc.settings=true
ro.sony.dlna_dms.enabled=false
ro.somc.social_product_model=PRODUCT_MODEL_TABLET
ro.sony.irremote.protocol_type=2
ro.sony.ols.eula=1
ro.pss.ps1content_disable=1
init.svc.ueventd=running
init.svc.recovery=running
init.svc.nfx_daemon=running
init.svc.radbd=running

-- Install /sdcard ...
Finding update package...
I:Update location: /sdcard/signed-nbx03_001-ota-120914044.zip
Desklunvr update package...
Opening update package...
I:1 key(s) loaded from /res/keys
Verifying update package...
I:comment is 1465 bytes; signature 1447 bytes from end
E:failed to verify whole-file signature
I:verify_file returned 1
E:signature verification failed
Installation aborted.
Starting recovery on Mon Oct 7 08:27:48 2013
can't open /dev/tty0: No such file or directory
framebuffer: fd 3 (1280 x 800)
recovery filesystem table
=========================
0 /tmp ramdisk (null) (null) 0
1 /hwconfigs ext2 /dev/block/mmcblk0p1 (null) 0
2 /configs ext4 /dev/block/mmcblk0p2 (null) 0
3 /system0 ext4 /dev/block/mmcblk0p3 (null) 0
4 /system1 ext4 /dev/block/mmcblk0p4 (null) 0
5 /cache ext4 /dev/block/mmcblk0p5 (null) 0
6 /misc emmc /dev/block/mmcblk0p6 (null) 0
7 /staging ext4 /dev/block/mmcblk0p7 (null) 0
8 /blflags ext4 /dev/block/mmcblk0p8 (null) 0
9 /datapp ext4 /dev/block/mmcblk0p9 (null) 0
10 /log ext4 /dev/block/mmcblk0p10 (null) 0
11 /data ext4 /dev/block/mmcblk0p11 (null) -32768
12 /sdcard vfat /dev/block/mmcblk1p1 /dev/block/mmcblk1 0
13 /boot emmc boot (null) 0
14 /recovery emmc recovery (null) 0
15 /system ext4 system (null) 0
16 /vendor0 ext4 vendor0.img (null) 0
17 /vendor1 ext4 vendor1.img (null) 0

Command: "/sbin/recovery"

ro.boot.serialno=015d32205e300c0d
ro.boot.commchip_id=0
ro.boot.bootloader=0x00000009
ro.bootmode=unknown
ro.baseband=unknown
ro.bootloader=0x00000009
ro.hardware=txs03
ro.revision=0
ro.factorytest=0
ro.secure=1
ro.allow.mock.location=0
ro.debuggable=0
persist.sys.usb.config=mtp
ro.build.id=TJS0166
ro.build.display.id=TJS0166
ro.build.version.incremental=130329002
ro.build.version.sdk=16
ro.build.version.codename=REL
ro.build.version.release=4.1.1
ro.build.date=Fri Mar 29 00:51:21 JST 2013
ro.build.date.utc=1364485881
ro.build.type=user
ro.build.user=integ-build
ro.build.host=build5
ro.build.tags=test-keys
ro.product.model=SGPT12
ro.product.brand=Sony
ro.product.name=SYS_052
ro.product.device=txs03
ro.product.board=txs03
ro.product.cpu.abi=armeabi-v7a
ro.product.cpu.abi2=armeabi
ro.product.manufacturer=Sony
ro.product.locale.language=en
ro.product.locale.region=US
ro.wifi.channels=
ro.board.platform=tegra
ro.build.product=txs03
ro.build.description=SYS_052-user 4.1.1 TJS0166 130329002 test-keys
ro.build.fingerprint=Sony/SYS_052/txs03:4.1.1/TJS0166/130329002:user/test-keys
ro.build.characteristics=tablet,nosdcard
ro.opengles.version=131072
wifi.interface=wlan0
wifi.wpa_supp_ready=0
persist.tegra.nvmmlite=1
ro.sf.override_null_lcd_density=1
keyguard.no_require_sim=true
debug.nfc.fw_download=false
debug.nfc.se=false
ro.ril.wake_lock_timeout=200000
ro.streaming.video.drs=true
ro.tether.denied=true
ro.sony.sound.enabled=true
ro.sony.irremote.devicefile=/dev/ttySIR0
ro.sony.autovolume.threshold=10
ro.product-res-path=vendor/framework/SemcGenericUxpRes.apk
ro.sony.update.server=info.update.sony.net
ro.sony.update.category_id=ST001
ro.config.alarm_alert=Alarm.ogg
ro.config.notification_sound=Notification.ogg
ro.config.ringtone=Ringtone_XPERIA.ogg
ro.carrier=unknown
drm.service.enabled=true
dalvik.vm.heapstartsize=8m
dalvik.vm.heapgrowthlimit=64m
dalvik.vm.heapsize=384m
ro.semc.enhance.supported=true
ro.semc.clearaudio.supported=true
ro.somc.dmnorm.supported=true
ro.sony.wifisleep=0
ro.sf.lcd_density=160
ro.setupwizard.mode=DISABLED
ro.com.google.gmsversion=4.1_r4
ro.com.google.clientidbase=android-sony
dalvik.vm.dexopt-flags=m=y
net.bt.name=Android
net.change=net.bt.name
dalvik.vm.stack-trace-file=/data/anr/traces.txt
tf.enable=y
ro.sony.wan.ipv6.enable=false
persist.sys.sony.cabc.disable=0
persist.sys.sony.hdmi.disable=0
ro.sony.cradle.settings=true
ro.sony.hdmi.settings=true
ro.sony.cabc.settings=true
ro.sony.dlna_dms.enabled=false
ro.somc.social_product_model=PRODUCT_MODEL_TABLET
ro.sony.irremote.protocol_type=2
ro.sony.ols.eula=1
ro.pss.ps1content_disable=1
init.svc.ueventd=running
init.svc.recovery=running
init.svc.nfx_daemon=running
init.svc.radbd=running

-- Install /sdcard ...
Finding update package...
I:Update location: /sdcard/signed-nbx03_001-ota-120914044.zip
Desklunvr update package...
Opening update package...
I:1 key(s) loaded from /res/keys
Verifying update package...
I:comment is 1465 bytes; signature 1447 bytes from end
E:failed to verify whole-file signature
I:verify_file returned 1
E:signature verification failed
Installation aborted.