Water Dripping Sound While on Highway

[PENN]

Today I heard a water-dripping sound (almost like a steady trickle) in the cabin while on the highway (65+mph).
I wasn't sure if it was related to the A/C?
I did have the A/C on, but then turned it off when I heard the sound, and the sound continued to persist.

First time hearing this.

Any ideas?

 

[TyphoonFiST]

Coolant in the Heater core?

 

[PENN]

Coolant in the Heater core?

Sorry, do you mind explaining that a little more? Thanks.

 

[TyphoonFiST]

Coolant flows through the heater core and makes whooshing sounds or water gurgling. Check your overflow to see if the coolant is full also.

 

[Clint Beastwood]

Drain hole for the ac plugged somewhere maybe - other fisters, possible in FiST?

 

[PENN]

Coolant flows through the heater core and makes whooshing sounds or water gurgling. Check your overflow to see if the coolant is full also.

Thanks!