My iPod got damage by rain

Ahh, the famous rice myth once again...

The water is inside the iPod, on the logic board and under the shields, even under the IC's. The rice is nowhere near where the water is. So while it ‘’may’’ soak up some water vapour, the real problem is the mineral deposits that can cause short circuits or the corrosion that is taking place as the water evaporates. Leaving the power on the device accelerates the process. The longer you let a phone sit in rice, the more time you are giving corrosion to damage your logic board. The saltier or harder the water is, the more damage will occur. The water needs to be displaced, not heated and evaporated.

So here are some things you can try:

• Open your device and remove the logic board (follow this guide)
• Inspect the logic board, especially around the connectors and look for corrosion.
• Inspect both sides of the board.
• Put your board in a container with >90% isopropyl alcohol and let it sit for a while.
• Use a soft brush, like a toothbrush and lightly brush away any corrosion you see.
• Rinse in alcohol and repeat.
• Let it air dry for a day.
• Re-assemble and hope for the best.

You should also consider getting a new battery if it has swollen. Resist the temptation to pop it to let the gas out. A compromised Li-ion battery is a fire hazard.

A professional repair shop that does water damage repair may be able to recover your device because they have access to pro-level ultrasonic baths and specialized cleaners as well as the skills to troubleshoot your board. Many shops have a no fix/no fee policy so you don't have to spend money to find out if the device is fixable or not.