@Kailash *******
I had no problem with my UK embassy letter 2 weeks back. The UK embassy needs to see 'evidence' of where the funds cone from and include this detail in their affidavit. My understanding is the U.S. embassy requires no proof other than its citizens say so and signature.
I read on this feed 10 days back that Chiang Mai were now also wanting to see proof of funds to backup U.S. embassy affidavits.