When i accelerate it sounds like a hole in my muffler, but when I maintain a constant speed it goes away, what can it be?

Likely a loose heat shield. Trace the exhaust system from the engine to the back, check all heat shields to be tight and not bent close enough to exhaust or body to cause the rattle while running.

Could be a loose element in the muffler that vibrates at certain engine RPM. Or a small hole in the muffler. Sometimes the problem is as simple as a loose clamp, either a clamp that holds the muffler to the chassis or a clamp that joins two exhaust pipes. A loose clamp can allow the muffler or pipe to vibrate against the frame. Clamps are cheap - a lot cheaper than a new muffler or exhaust system.

Defective clutch release bearing is a possibility.

Check A.I.S./I.A.C. motor on throttle body. Known by both names, Automatic idle speed motor (AIS) Idle Air control (IAC) . Usually mounted on side of throttle body, with 2 or 3 torx screws and it's job is to adjust idle at all times as necessary, such as when AC on, turning, etc when extra load on engine, it will increase idle as needed to overcome the load and maintain proper idle speed. You can often remove the motor and clean pintle (pointed end that goes inside throttle body) with throttle body spray cleaner as well as spray inside the port (hole) that it comes out of. Sometimes this will cure the problem for quite a while, but if only for a short time, and it happens again, replace it.

Sounds like you have a defective universal joint or constant velocity joint in the drive line.

What speed are you going when it chugs?
It could be as simple as a bad spark plug or a spark plug wire/boot grounding out.
When spark plug boots get old, the rubber cracks and lets voltage arc out the side and to the engine instead of through the plug.
This will be most noticeable when trying to maintain a speed of over 40 mph, or under mild acceleration.
The reason for being noticeable at this speed/acceleration level is that the transmission torque converter will be locked, transferring the vibration from any engine miss straight through to the wheels.

loose belt

your catalytic converter/s is/are plugged.
there is 2 of them coming out of both banks ( sides) of the motor. they join to one main pipe that goes to the muffler at the back of the vehicle.

you can take it to a muffler shop and they can test the pressure in your cat. converters for cheap or free. that will tell you if they are wrecked or not.

i would get it checked out asap because if your cats are the problem they well break your o2 sensors for the cats.

if you need to fix them you can do it cheeply by drilling holes in the cats to let the air out.

hope this helps

COULD BE THE ENGINE CONTROL UNIT.
A PROBLEM FOR HONDA.

If you ever have an oil leak it really should be fixed right away unless this happened all at once. Go to a local mech or if there is an Autozone around go there and have them check the Engine Light code for you for free. You will have more info to work with.