when debugging SAI audio on Vybrid (PVF61GS151CMK50 1N02G), we encountered problem with PTB18 behaviour. When IOMUXC_PTB18 MUX set to 0x02 (master clock), it does not output clock.
In GPIO mode (MUX 0x00) does not work properly in CMOS mode (ODE 0), works only as open-drain (ODE 1).
Tested on two MCUs with the same result.
Is this a known issue? Is there any workaround to make audio working on TWR?