As you said yourself, it was most likely a rendering issue. A bad low-pass filter would have attenuated the high-end when converting to 44khz. Also, this is afaik the reason why all modern audio uses 48khz, you get a little bit more head-room when designing a low pass filter and you can even choose a less aggressive and perhaps less computationally expensive one that still won't have an effect on the humanly perceptible frequencies.
I think the reason a lot of modern audio is at 48k has more to do with it being accompanied by video, which has independently settled on sampling rates of 48k, 96k, etc.
