DNS listeners, DNS Express & BIND

A wip should always be resolved with gslb never dns express or bind. Do the wip pool stats show that the fallback lb method is being used? If the fallback method is set to "Return to DNS" then gtm has given up on intelligent gslb resolution and will attempt standard resolution using express/dns pool/bind. If your wip is not being resolved with the preferred or alt lb methods then something is wrong with the gslb config. Resolving a wip does not require bind or express to be enabled in the listener dns profile. Can you post the gslb config from /config/bigip_gtm.conf?