Sundara is rated 92 dB/mW at 32 Ohms by Hifiman and 90 db/mW at 40 Ohms by the ASR review. Only 8 mW are needed to get to 98 dB, so I’m pretty sure you are pushing your cans way past this sound level fogure. The only sensible way to know if your amp is defective is measuring the output power just when the protection kicks in.With Sundara and all chain in balanced i cannot reach 110dp spl ..... because at around 98db my topping A70 goes in protection. Im very disappointed