Next number sequence

Be forewarned: this is a riddle in the spirit of riddles.

Given the following:

...4522222222255555555599999999

What are the next digits?

Note: I did not specify the number of digits you should give, because, if you know the answer, you can continue to correctly add an arbitrarily large number of digits.

I could ask you give the next 4 or 5 digits, but you would probably want to give more than 4 or 5 digits.

Hint:

the next 7 digits are 999999999

...But why?......

Sound out what you see... 3 dots, 1 four, 1 five, 9 twos, 6 fives, followed by 3 fives, then 8 nines.