Fix bug #2226

[magiclin99]

Context:

Please refer to #2226

Root cause:

In vars.xml , when you use codec settings like this:
<X-PRE-PROCESS cmd="set" data="internal_codec_prefs=OPUS@16000h@1c,PCMU,PCMA,G729"/>

The switch_core_media.c line 5520 only takes the OPUS default rate (48k) instead of 16k in the config.

Because of this, FS won't be able to choose opus if your client asks for 16k opus. You will see same log symptom as #2226

Solution

uint32_t codec_rate = imp->actual_samples_per_second;