Hi!
The voicemail problem in the US is mostly a caller ID reputation issue, not a dialler issue. US carriers flag unknown international numbers as spam before they even ring.
Two quick fixes:
First, get US local numbers for your SDRs. Aircall supports this. Make sure you are dialling from area codes that match the prospect's region. Local presence dialling alone can double your connect rates.
Second, warm up the prospect before calling. Quick LinkedIn profile view or comment, one Smartlead email, then the call. When they recognize the name, they pick up. Cold calling the US from India without any prior touchpoint is almost zero connect rate now.