Dear Marsilians,
Thanks a lot for your help.

If you have the names of the Denon guys in Singapore, then probably I can write to them directly. I knew one Mr Jimmy Quek at D&M Singapore, but unfortunately while all this was going on, I tried to contact him, but his e-mail does not seem to work.
But, in any case, I do plan to take them to the consumer court... I have lawyer freinds and they are not busy these days.....

I dont even mind spending the money, the trouble these people gave me

)....But, atleast, I will make their life a bit tough for a while also. You never know, it might help a lot of our other freinds who might have been subject to similar black mailing.
The fact that PROFX accepted my AVR for repairs and gave me an estimate by paper for labour, the fact they called me the next day and informed me about the blown transistor and repairs were minor, the fact that they sent me sms, the fact that they never gave me an estimate of cost of spare parts for my approval if the cost was going to be 20% higher than estimated. They did not even let me know the details of the parts, even on my insisitance(sms exchanges with their service and Sales), the fact that on delivery, they never gave me a break-up of repairs but just a receipt saying "service charges Rs so and so "....
They never took approval for repairs from me, They never gave breakup of labour and parts, they never returned failed parts inspite of my insistance. The service chages charged are just adhoc. All these points have been mentioned on the delivery challan when I made payment and took the repaired AVR subject to these conditions.

I am sure all the above are good enough to take them to the consumer court...and of course I will also be claiming for the mental agony they gave me during these 47 days.
I dont know whether I should be writing all the above on this forum... but since you enquired...