What is this condition called?

[Guest guest]

My 3 year old with autism has started talking but he replaces his consonants.

For example:

he says baba for mama

oten for open

poes for toes

taty for baby

jump is dump

bye bye is thay thay

close is pose

he replaces t's for p's and vice versa and likewise other consonants. I am

wondering how I can help him. Also his voice is very soft and tends to fade

away. Does this improve ?

Thanks,

Maya