5Mhz Tx

I’m trying to generate 5Mhz using Lime SDR USB and GNU radio. But power level is changing a lot.
The following massage contiguously displaying

“popping from TX, samples popped 0/1020”

please kindly let me know you suggestion.

Hello Thisara,
Samples from TX are getting popped because you are not giving enough samples to the Sink block before it timeouts, that’s why your power level is changing and the signal might even disappear.
Could you post the flowgraph you are using?