From dmesg in knoppix 7.2:

ath5k_hw_get_isr: ISR: 0x00000080 IMR: 0x00000000

From Linux/drivers/net/wireless/ath/ath5k/dma.c

if (unlikely(*interrupt_mask == 0 && net_ratelimit()))
731 ATH5K_PRINTF("ISR: 0x%08x IMR: 0x%08x\n", data, ah->ah_imr);
732
733 return 0;
734 }

Wireless going up and down. This didn't happen in previous versions of knoppix.

Maybe just get an external wireless adapter??