[regression] Assert in BASOP encoder with MASA LTV rate switching
# Basic info
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- Fixed point:
- Encoder (fixed): 383e7f47f5f36f6bc43d833184b663ec40360d4d (also main but according to git bisect, this introduced it)
# Bug description
Based on LTV run, there is a new LTV crash in MASA rate switching. Based on git bisect, this was introduced in MR !2326. Stack trace below

# Ways to reproduce
<!-- Commandline or script -->
```bash
./IVAS_cod -masa 2 ltv48_MASA2TC.met sw_13k2_512k.bin 48 ltv48_MASA2TC.wav debug.bit
```
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issue