Noise most likely caused by faulty gear cable or to a lesser extent, gearbox related issues such as the bearings.

This whistling noise is audible after hitting around 60 kph n is continuous. Affects quite a number of bezza. It is a known issue and the service center service technicians described it as "bunyi siul". They have located the source and confirmed it to be caused by a faulty "CABLE ASSY, TRANSMISSION CONTROL" part number 33820-BZ300.

The aircond whisling sound is faint relative to that emanating from the faulty transmission cable. However, it is conspicuous to drivers of the ADV (full spec) variant once the i-stop kicks in during which the engine shuts down. I think most drivers facing this minor noise can afford to tolerate it.

Bezza + pb combo make the car responsive and fun to drive especially in the city and short distance highways.

Ur aircond seriously need to go for an inspection. Find a SC with experienced and knowledgeable technicians.
Nuff said about the transmission cable. Suggest u to make an appointment with ur service center to get the cable replaced. Prepare to wait for 2 weeks for the part to arrive. Its foc btw. Pls dun ask me to explain the technical aspect of the fault. As mentioned earlier, its a known issue.
Pb serves to remap the signal to the throttle resulting in a more responsive, spirited n pleasurable drive. Try it, I'm sure u will like it.

On the bad handling and stability issue
I have driven the 2 bezza auto variants, i.e., ADVANCE n Premium X countless times over long distances and at various speeds and opine that the vehicle stability of:
- the PREMIUM X is highly susceptible to crosswind when the car reaches a mere speed of  just 90 kph. At this speed the car begins to sway from left to right and vice versa on its own even if the steering wheel is held firmly. For comparison, a stock Axia G with no electronic control assist and no stability bars installed can travel up to 140 kph without being affected by crosswind.
- the PREMIUM X (this time with ARB + FSB installed) is LESS susceptible to crosswind at speed of under 140 kph, Above that, it begins to sway.
- the PREMIUM X (this time with ARB + FSB + Bi Spring installed + 15" Alza rim) is almost not affected by crosswind even if the car is driven up to its maximum speed of around 170 kph. (some claim that  max speed of bezza is a whopping 190 kph). Notice that the braking power of bezza X is not strong, advise drivers to keep the max speed under 140 kph.
- the ADVANCE (totally stock) is surprisingly VERY good. Crosswind effect is almost negligible even at max speed. The electronic VSC and traction control certainly have played a vital role in  keeping the car in a straight line despite attempt by crosswind trying to unsettle it.
So is it worth to spend 6K more for an ADVANCE variant? My answer is a thumping YES. If u r driving Premium X, advise u to at least install ARB + FSB for a start.

ARB = UR anti roll bar 16mm (u already quoted it)
FSB = front strut bar
Both items cost around 600+

ARB is not a standard accessory in the ADVANCE variant
but
ARB is a standard accessory in the new Myvi 1.5. However, its diameter is a puny 12 mm measured on a caliper.

Try to google bi spring. Easily done. Cost 380/pr inclusive of installation

All the items r just plug n play. No mod required.

Mine is 1.3, luckily I read the service manual on the first post. SA ask me to change it along with many other things that I don't need.

Another story from the same service centre, seems that they forgot to close back the cap for my battery and the liquid splash all over my engine bay. I traveled for 2 days for more than 300km already after service. I only got to know about this when I installing axa flexdrive today.

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Need advice on how to deal with service agent regarding this so I don't lose out anything

This is a ridiculous mistake. The pic shows where they left the cap. If I did not install the flexidrive I confirm wouldn't know it until my battery KO or irreversible damage on my engine bay

Lol
True..
Spend on nvh..

I  notice bending there, whether this is factory defects or after 2 months used. Should I claim for replacement.

that link doesnt show any information, guess they wwanna hide the price so each sc can charge differently?

This whistling noise is audible after hitting around 60 kph n is continuous. Affects quite a number of bezza. It is a known issue and the service center service technicians described it as "bunyi siul". They have located the source and confirmed it to be caused by a faulty "CABLE ASSY, TRANSMISSION CONTROL" part number 33820-BZ300.

Which SC was that?

Your high pitch sound is continuos? Is the sound still there when you release the accelerator pedal? For my case the high pitch sound @ 80km/h will disappear once I release the accelerator pedal. That tells me the sound is coming from the throttle body.

worried about retaliation? 

Hi guys, its it advisable to go for this Bezza 1.0 GXtra or the Axia Standard G? In terms of issues, maintenance, quality. Basically looking for a car to drive around town and occasionally outstation for my parents. Considering between these 2 cars.  Thanks

I see thanks for your input, what about the 1.0 for Bezza? Does it feel underpowered for a sedan?

hi.. im considering to buy bezza adv or low spec alza..

my considering base on below aspect;

1. space
2. fuel consuption
3. comfort

my driving usually on city drive on weekday and highway on weekend.. which one between this 2 cars do u think is more suitable for me?

not sure man..
not even sure if i hear it in my car....
i'll pay more attention next time...
but initially, i'd say that there's nothing wrong???

i know that noise. Saw few complain from facebook. its like human whistle sound.
Some grab drivers embarrassed because their passenger thought they whistling LOL.

its coming from the air cond vent