sysmoBTS doesn't start

Hi guys, I have a sysmoBTS from sysmocom and last time i used it (for 3 weeks) everything was working well. Yesterday i wanted to do some tests and the device didn't start up. I think there are some problems by the booting process, here are the logging data: Board revision: C.3 Initializing NAND flash: Bypassing ECC checks ID:0xA1, 8-bit bus Blocks: 0x00400, Pages/block: 0x040, Bytes per page: 0x0800 BootMode = NAND I_ME UART_TIMEOUT Image infos: Magic = 0xA1ACED77, Entry = 0x84000000, Pages = 0x000000B9, Load = 0x84000000 Starting app at: 0x84000000 U-Boot 2011.12-g5ee9b97 (Aug 15 2012 - 21:35:37) Cores: ARM 405 MHz, DSP 810 MHz DDR: 189 MHz I2C: ready DRAM: 256 MiB WARNING: Caches not enabled NAND: 128 MiB Bad block table found at page 65472, version 0x01 Bad block table found at page 65408, version 0x01 nand_read_bbt: Bad block at 0x000000880000 *** Warning - bad CRC, using default environment In: serial Out: serial Err: serial Net: DaVinci-EMAC Creating 1 MTD partitions on "nand0": 0x000000100000-0x000008000000 : "mtd=3" UBI: attaching mtd1 to ubi0 UBI: physical eraseblock size: 131072 bytes (128 KiB) UBI: logical eraseblock size: 129024 bytes UBI: smallest flash I/O unit: 2048 UBI: sub-page size: 512 UBI: VID header offset: 512 (aligned 512) UBI: data offset: 2048 UBI: attached mtd1 to ubi0 UBI: MTD device name: "mtd=3" UBI: MTD device size: 127 MiB UBI: number of good PEBs: 1011 UBI: number of bad PEBs: 5 UBI: max. allowed volumes: 128 UBI: wear-leveling threshold: 4096 UBI: number of internal volumes: 1 UBI: number of user volumes: 1 UBI: available PEBs: 0 UBI: total number of reserved PEBs: 1011 UBI: number of PEBs reserved for bad PEB handling: 10 UBI: max/mean erase counter: 71/16 has anybody an idea how i can overcome this problem ? best regards Yann