Problém vznikl při videohovoru.

Vznikl means arose, came up, or occurred.

Its dictionary form is vzniknout, which is a perfective verb. In this sentence, vznikl is the past tense masculine singular form, matching problém, which is a masculine noun.

So:

• vzniknout = to arise / to come into being / to occur
• vznikl = arose / occurred

In this sentence, Problém vznikl literally means The problem arose.

Czech usually does not use a separate verb meaning was in sentences like this.

In English, you might say:

• The problem arose during the video call.

In Czech, the past tense is often formed with:

• a past participle-like form such as vznikl
• sometimes also an auxiliary, depending on the person

In the 3rd person singular (he/she/it), the auxiliary is usually omitted:

• vznikl = he/it arose
• vznikla = she/it arose
• vzniklo = it arose

So Problém vznikl already fully means The problem arose.

Because the preposition při requires the locative case.

The base noun is:

• videohovor = video call

After při, it changes to:

• při videohovoru = during the video call / in the course of the video call

So the ending -u shows the locative singular.

This is a very common pattern:

• při hovoru = during the call
• při jednání = during the meeting
• při práci = while working / during work

Here při means something like:

• during
• in the course of
• while

So:

• při videohovoru = during the video call

Be careful: při does not always translate the same way in every sentence. Its core idea is often in the course of or in connection with something.

For example:

• při studiu = during one’s studies / while studying
• při práci = at work / while working
• při nehodě = in the accident / during the accident

Yes, you often can.

Both can mean during the video call, but there is a slight difference in feel:

• během videohovoru = more directly during the video call
• při videohovoru = during / in the course of / in connection with the video call

In this sentence, both are natural:

• Problém vznikl při videohovoru.
• Problém vznikl během videohovoru.

The version with při can sound a little more formal or neutral in some contexts.

Because problém is a masculine noun.

In Czech past tense, the verb form agrees with the gender and number of the subject.

• problém is masculine
• therefore: vznikl

Compare:

• Problém vznikl. = The problem arose.
• Chyba vznikla. = The error arose.
  (chyba is feminine)
• Nedorozumění vzniklo. = A misunderstanding arose.
  (nedorozumění is neuter)

It can often mean either, depending on context.

Czech has no articles like a and the, so problém by itself does not tell you whether it is definite or indefinite.

So Problém vznikl při videohovoru could be understood as:

• The problem arose during the video call
• A problem arose during the video call

You decide from context which is more natural in English.

No, Czech word order is fairly flexible, although different orders can sound more natural in different contexts.

The neutral version here is:

• Problém vznikl při videohovoru.

But other orders are possible, for example:

• Při videohovoru vznikl problém.
• Při videohovoru problém vznikl.

These can shift the focus slightly:

• Problém vznikl při videohovoru. → focus starts with the problem
• Při videohovoru vznikl problém. → focus starts with during the video call

In many cases, Czech word order is influenced by what is already known and what is new information.

Yes, nastat is also possible in many contexts.

Compare:

• Problém vznikl při videohovoru.
• Problém nastal při videohovoru.

Both are natural and both can mean The problem occurred during the video call.

A rough difference:

• vzniknout = to arise, come into being
• nastat = to occur, take place, happen

In many everyday sentences about problems, the two are very close in meaning.

Roughly:

• vi-de-o-ho-vo-ru

Each vowel is pronounced clearly. Czech pronunciation is usually more regular than English spelling.

A rough English-friendly guide might be:

• VID-eh-oh-HOH-voh-roo

Stress in Czech normally falls on the first syllable of the whole word:

• VIdeohovoru

But remember that Czech stress is usually lighter and more even than English stress.

Yes, it is common and understandable, especially in modern everyday language.

It means:

• video call

Related words:

• hovor = call / conversation
• telefonní hovor = phone call
• videokonference = video conference
• volat = to call

So videohovor is a normal modern compound noun: video + hovor.