PLC quality issue MDCT stereo at 48kbps

This is an issue regarding the outlier from subjective verification testing at this operation point (see 6.1.3.2 of Report S4-242054 ) . This item scored almost 1 MOS worst than the floating point version. Checking the latest main version 196fb050 the issue is still there and even more pronounced than in the version in the listening test.

Below is the difference of the two signals (float-fixed):

There are larger differences in general with the onsets, but what degraded the perceptual quality of the CuT are the plops that are outlined in the circles that appear at the tonal part of the signal.

I uploaded the bitstream in the box folder.

To reproduce ./IVAS_dec stereo 48 glock_bit.err.192 out.wav