We recommend that you use your ISPs DNS servers. The way that CDNs decide what POP to direct you to is based on the DNS lookups that your device does via the DNS servers specified. Unfortunately we have witnessed a number of times where the CDNs that are used by TVE networks will pick a POP that is across an over-saturated link instead of the POP that is local to the ISP of the client. (I've also seen this behavior from Netflix and others).
To clarify, are you mixing 18.104.22.168 and 22.214.171.124 and using both of them at the same time? This is really the worst case scenario for streaming and can cause your requests to jump from one POP to another as DNS caches timeout and new requests happen.
Mixing DNS providers can cause "Transcoder Reset" errors due to network propagation delays causing m3u8's to go back in time.
We've had a number of support requests recently that were related to slow requests and timeouts on TVE streams and m3u8's going back in time, so are starting to try to add to our troubleshooting list to highlight these potential issues.