I've been experiencing a reproducible issue with my Viper V4 Pro whenever the polling rate is set to 125 Hz.
It starts with the mouse cursor randomly stuttering. A few seconds later, the mouse disconnects from the wireless dongle, and both the mouse and the dongle start blinking while they reconnect. After a few seconds, the connection is restored and everything works normally again.
My previous mouse was the Viper V3 Pro, so I'm used to enabling the automatic polling rate switching in Synapse to save a bit more battery life. I normally use 125 Hz on the desktop and 1000 Hz while gaming.
At first, I thought the issue might be related to Synapse automatically switching between polling rates, but that's not the case. The exact same problem also occurs if I manually set the polling rate to 125 Hz and leave it there. If I keep the polling rate fixed at 1000 Hz or above, the mouse works flawlessly. I haven't experienced a single disconnect or cursor stutter in that configuration.
This makes me believe the problem is specifically related to the 125 Hz polling rate rather than the automatic polling rate switching feature.
I've already updated the firmware and used the pairing utility to re-pair the mouse, but the issue persists.