SimpleAudioEngine playEffect() slow on HTC Wildfire S

I have a wide range of Android devices and for some reason the HTC Wildfire S is the only device which is dropping FPS when playing sound effects via SimpleAudioEngine->playEffect. I’ve tried changing the audio format from WAV to OGG and saw no difference. Other devices with similar hardware have no issues. Is there a known problem with the HTC Wildfire S, or some tips for playing effects more efficiently on slower hardware? All of the sounds are preloaded ahead of time. The old Amazon Kindle Fire 1st Gen and Sony Xperia ray are of a similar age and have no problem. My game runs at a solid 60 FPS until a sound effect is played.