This sounds like a hostile take over by the root stalk of your plant. The yellow rose was grafted onto a hardier root stalk years ago but sometimes that graft goes bad and a bud from down low sprouts from the original wild rose from the roots and as it is more vigorous it can take over the hybrid rose. The solution is to follow each red blooming cane or branch down to where it emerges from the ground and cut it out as close to the main stalk as you can. Keep cutting these suckers out if they reappear and your original rose will most likely be able to get control of the situation once again. Now pamper the newly pruned rose with fertilizer, extra water and a mulch of wood chips or compost that will cover up the growth points on the root stalk that has been sprouting those aggressive suckers. Stick with the pruning of the wild shoots and your lovely rose will reappear. Keep growing, Marianne Binetti