Git SHA:e7a2525e314c5780dcd73dda8fd5fa692237b6c8 Using an internal test file (which will be shared separately), an assert is triggered during lost frame concealment in the TCX stereo decoder. Reproduce with (error pattern file can be found [here](https://forge.3gpp.org/rep/ivas-codec-pc/ivas-codec/-/blob/main/ci/complexity_measurements/ep_10pct_fer.g192)): ``` shell ./IVAS_cod -stereo 32000 16 input_signal.wav bit eid-xor -fer -vbr bit ep_10pct_fer.g192 bit_err ./IVAS_cod stereo 16 bit_err out.wav ``` This triggers an assert at `basop32.c:1665` due to an overflow happening. The relevant context is this code from `tonalMDCTconcealment_fx.c:1660`: ``` c tmp = div_l( nrgNoiseInLastFrame, round_fx( nrgWhiteNoise ) ); ``` The saturation happens in `round_fx`. The variable `nrgWhiteNoise` contains the energy of a generated white noise spectrum which is accumulated and used in this line to calculate a normalization factor for the whole spectrum that intends to scale the spectrum to a certain energy (i.e. `nrgNoiseInLastFrame`). This energy accumulation should ideally not saturate to achieve the intended scaling.