Are you sure its running at 0.8 MHz and not 1 MHz? Sounds like you forgot to "Burn Bootloader" to set the fuses and the factory default 1 MHz fuses are still in effect.
Are you sure its running at 0.8 MHz and not 1 MHz? Sounds like you forgot to "Burn Bootloader" to set the fuses and the factory default 1 MHz fuses are still in effect.