Modulation artifact in OMASA at 24 kbps using LTV 3ISM 2TC input and output to MONO

Basic info

• Encoder (float): d18cbee3
• Decoder: 4e6c6d71

Bug description

Using the LTV test vector set of

ltv48_OMASA_3ISM_2TC_ISM1.csv
ltv48_OMASA_3ISM_2TC_ISM2.csv
ltv48_OMASA_3ISM_2TC_ISM3.csv
ltv48_OMASA_3ISM_2TC.met
ltv48_OMASA_3ISM_2TC.wav

there seems to be present some modulation artifact at about 6s into the sample (violin + other instruments playing) which is not present in the float versions.

As this is 3ISM at 24.4 kbps, this means that OMASA should be in the PreRend path.

Ways to reproduce

Using the LTV test vectors, use following commands

IVAS_cod_flt_ref -ism_masa 3 2 ltv48_OMASA_3ISM_2TC_ISM1.csv ltv48_OMASA_3ISM_2TC_ISM2.csv ltv48_OMASA_3ISM_2TC_ISM3.csv ltv48_OMASA_3ISM_2TC.met -max_band fb  24400 48 ltv48_OMASA_3ISM_2TC.wav test.bs
IVAS_dec MONO 48 test.bs out.wav