Kinda thinking aloud here:

44100 / 8000 is almost 5.5.
8000 * 5.5 = 44000
Close enough that the playback speed would be off by 0.23%. Prolly not enough to make a difference for TTS.

Off hand, I don't know how to do the half in there. If you read in pairs of samples and output 11 at a time, how do you do it?
A: input = (-14, 120) output = (-14, -14, -14, -14, -14, -14, 120, 120, 120, 120, 120)
B: input = (-14, 120) output = (-14, -14, -14, -14, -14, 53, 120, 120, 120, 120, 120)
C: none of the above... something better.

At least A and B would be pretty easy to program and not very CPU intensive.