K8060 bandwidth

The bandwidth of the amplifier is specified at 200kHz, but with maximum output level I face a problem with strong distorsion and even at the end the sinus to become a triangle with reduced amplitude for freqencies above 20kHz.
At the beginning of the distorsion, we see clearly that it is a problem of slew rate.
Is this problem inherent to the design or is there a problem with some component on the board?
I already changed T2 and T3 without any improvement.

Hi, is this problem solved?

Just a thought.
Most humans can only hear around 20Hz to 20kHz
I wonder if when they made the specs of the K8060 if an extra “0” was added and missed.

Like I said just a thought