Yeastar Technology Tiptel 31 Configuration Manual page 6

6. Next, we need to configure the audio codecs. Click on the "Account/Codec"
tab. Ensure that the "Enable codecs" list box contains first "G722", then
"PCMU", and finally "PCMA". Click the "Confirm" button at the bottom of the
page.
7. We also need to configure the phone to subscribe for MWI notifications. Click
on the "Account/Advanced" tab:
1) Set the "Subscribe MWI" field to "Enabled"
2) Click the "Confirm" button at the bottom of the page
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Tiptel 31XX IP Phone Configuration Guide
Figure 1-3
Figure 1-4
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