I had a obi202. The two phone port light keep blinking even no phone are connected. (keep showing on and off pattern every 2 seconds). When connected to phone, there is no dial tone. Can not make any phone call. The current firmware build is 4420. Tried to downgrade to build 4350. Not sure if 4350 is more stable than 4420. The device prohibited the downgrade.
Please give me some help here. Thank you.
