Noise diagnosis over the internet. WOW.
Drop the pan and replace the filter/screen. Do not over tighten the bolts. 75 in-lbs on 5/16"-head bolts, 10 ft-lbs on 1/4" thread bolt.
If noise is still there, get ready for a trans. Could be converter or pump whine. Either affects the other. Like oil and filter in an engine. Change both of them.
The C4 pump is notorious for wearing under load and once worn will cause RPM sensitve noise.
Pray the filter is plugged or torn....