I have played Bust-a-bit when I was new in cryptocurrency and the worst that I had come across so far was 5 streak in a row. I usually stop playing for a few rounds when this occurs. I tried figuring out when it usually occurs but I guess this is random since each run is generated by a random algorithm.

Also, martingale doesn't work long-run which everyone is already aware of. Have tried this several times before and if you will keep repeating it for the long run you will end up bankrupt.