cpuminer (minerd) strange problem

[alicea]

Hello
I have some strange problem with cpuminer (minerd).
Until previous weekend it runned on several computers (1. Ubuntu 10, 2. Win XP, 3. Win 7) and I received accepts one after another. No difference which computer and which system, one of them is faster, one is slower, but the situation was stable: statistically I received about 10-20 "yays", 1-2 "booos", and 1-2 lines with no response (I mean "detected new block" and nothing more).

I changed NOTHING and now it looks like this:

[2013-12-16 19:07:09] accepted: 1/1 (100.00%), 1.21 khash/s (yay!!!)
[2013-12-16 19:07:13] thread 1: 4096 hashes, 0.83 khash/s
[2013-12-16 19:07:16] LONGPOLL detected new block
[2013-12-16 19:07:16] thread 1: 3232 hashes, 0.88 khash/s
[2013-12-16 19:07:16] thread 0: 8928 hashes, 1.16 khash/s
[2013-12-16 19:07:27] LONGPOLL detected new block
[2013-12-16 19:07:27] thread 1: 9128 hashes, 0.84 khash/s
[2013-12-16 19:07:27] thread 0: 13064 hashes, 1.20 khash/s
[2013-12-16 19:07:36] LONGPOLL detected new block
[2013-12-16 19:07:36] thread 1: 7704 hashes, 0.86 khash/s
[2013-12-16 19:07:36] thread 0: 10184 hashes, 1.14 khash/s
then for example another 5 or 10 minutes with communicate "detected new block", till the next accept. Notice: I don't get "booos". And I have minerd version 2.3.2 but it makes no difference if I run this or other version, the result is the same...

I've tried without Stratum, and with Stratum again,
changed -t parameter from 1 to 12 (and finally left it auto)
changed -s parameter from 4 to 40 (and finally left it auto)
and so on. No use. What to do to make it work as before?

[1713951076]

1713951076

[1713951076]

1713951076

[1713951076]

1713951076

[1713951076]

1713951076

[1713951076]

1713951076

[1713951076]

1713951076

[vm1990]

what coin are you mining?

alot of coins have had serious hashrate dropped  on them the last 2 weeks so difficulty shoots up. which means its increadible hard for cpu miners to even get shares

cpu coins are
protoshares
primecoin

anything else will have big problems

[alicea]

what coin are you mining?

different minor coins

alot of coins have had serious hashrate dropped  on them the last 2 weeks so difficulty shoots up.

if you say "the last 2 weeks" then this is the solution of the problem, I think... Thanks!