Barracuda don't move

as there are no real moving parts on the barracuda, the pulse is driven by the efficiency of the pump. if there is air in the system, the pulse will slow down. as the air is expelled and the pump becomes more efficient at moving water, the pulse will increase.

its not uncommon to get some bubbles when using sectional hose as there are 12 connections that must be tight (but usually leak a bit). if you have access to a regular one piece hose, try using that to see if the problem corrects.
these machines are horrible for diaphragm problems which is why there is usually a big bin of replacements at every pool store. even though there is no tear, the rubber may have stretched or become rigid (water balance causes this)

Before you go anywhere I would check each piece of hose for leaks. If they are all OK then you need to plug off one end of the suction line and pressure it up at the other end. If the pressure drops then you have a leak in the line. I would check the fitting at the front of the pump first. Short of a cracked pipe that is where most suction leaks occur. This being a vinyl liner pool it could also be just behind the wall also.
If the hoses are Ok and it's not at the front of the pump you may want to get a leak detection service in to help find it. Good luck.

If you are seeing air bubbles in the leaf pot on the pump, you have an air leak on the suction side somewhere between the pump and the pool. Check the pump lid o-ring for any dirt, leaves, etc. Make sure the O-ring on the lid is not cracked, dry (lubrication like Aladdin's Magic Lube) or compressed or flattened. Also check your union or threaded connections to the pump suction (end) to insure they are tight and sealed. If this is an in-ground pool, and equipped with valves to control skimmers and bottom suction, close each valve separately to see if the air bubbles diminish. If the bubbles diminish when the valve is closed, then the air leak is in the closed section from that valve back to the pump. If the air leak increases, the air leak is in the still open line. Since the Kreepy crawly works on suction and increases the vacuum, the air leak will become more apparent, resulting in a loss of pump efficiency and flow, resulting in lost performance on the cleaner. If so equipped, close off the bottom drain valve and increase the suction on the vac line. I can provide further details as needed, but will need more information from you regarding actual equipment layout.

The Barracuda Zippy is an Above Ground pool cleaner and is not designed for a pool that does not have a flat bottom. They are generally not capable of climbing slopes, walls, etc.

You could have too much suction, something stuck in the diaprahm, a torn diaprahm could do this or if it is sticking to the drain you will have to shut the drain down.

Check your pump pressure on the suction side. If there is any air gap in your pump strainer pot (if you have a see thru see thru strainer cover) then you have a leak on the suction side. Auto matic cleaners need ample pressure for them to move. or you might need to backwask the filter check your pressure gauge. If none of these help its more then likely the gears in the cleaner. also check your cleaners hoses

Check suction at cleaner. Could be broken hose, bad or dirty impeller, incorrectly set valves, dirty filter, clogged line and probably a bunch more things.